Following are corrections for some errors that have occurred in my scientific publications and for which I would like to archive the accurate information.


Mills, C.E. 2000. The life cycle of Halimedusa typus with discussion of other species closely related to the family Halimedusidae (Hydrozoa, Capitata, Anthomedusae). Scientia Marina, 64 (Suppl. 1): 97-106.

I missed an important and relevant Chinese paper related to this study. It is:
Xu, Z. and Chen, Y. 1998. Life cycle of Tiaricodon coerules (sic) from Xiamen Harbour.
Journal of Oceanography in Taiwan Strait, 17(2): 129-133 (in Chinese).
A translation of some of this paper was provided to me by Dr. Peter Schuchert of Switzerland.
The authors note that Tiaricodon coeruleus occurs in Xiamen Harbour, China, from November to May and that it is especially abundant in January and February in salinities of about 13-22. They have grown the hydroid in the laboratory and it appears to be nearly indistinguishable from the polyp that I have grown from Halimedusa typus medusae, thus further verifying placement of Tiaricodon in the Halimedusidae. The Chinese paper features two plates of the developing hydroid of T. coeruleus.


Wrobel, D. and C. Mills, 1998 (first printing). Pacific Coast Pelagic Invertebrates - A Guide to the Common Gelatinous Animals. Sea Challengers and the Monterey Bay Aquarium, Monterey, California, iv + 108 pages.

Some factual errors or additions in the first printing have come to our attention and are noted below. The second printing of this book is due out in Spring 2003 and will correct all known errors, included many bits not listed here.

Cover. Upper left photo is Gonionemus vertens, upper right photo is Pelagia colorata (now Chrysaora colorata - changed by Lisa Gershwin).

p. 26, Photo 5. The species illustrated is Amphinema turrida, although the text description is of A. platyhedos. Anita Brinckmann-Voss pointed out that our photograph matches well the description and line-illustration of A. turrida, a seemingly warm-water, little-recorded, medusa whose previous nearest collection is the Pacific coast of Mexico (Kramp, 1961).

p. 29, Remarks about Photo 13. Medusae of the European species Cladonema radiatum are essentially indistinguishable from medusae of the Japanese species Cladonema uchidai; both appear to have been introduced on the west coast, living in similar habitats as the relatively uncommon native west coast Cladonema californicum.

pp. 29, 95, 98, 103, 107. The name of Maeotias inexspectata is more correctly given as the older name Maeotias marginata. This species has been returned to the Olindiidae in the Limnomedusae.

p. 37. Vallentinia adherens has also been collected in Santa Barbara. (Thanks to Erik Thuesen and Shane Anderson.)

p. 43. Center Photo 56 shows Crossota rufobrunnea on the left and Crossota alba on the right.

p. 45. Note that the common name for Physalia physalis is the Portuguese-Man-of-War.

p. 47, Photo 67 is Diphyes dispar. Photo 70a may be Praya, but it is more likely Rosacea sp. Photo 71 is Sulculeolaria quadrivalvis (all new identifications thanks to Philip Pugh). Photos 67 and 71 should have been mounted vertically with swimming bells uppermost, in the postures typical of these species, but the page wouldn't go together that way.

pp. 54, ii, 21, 23, 99, 103, 106-7. The name of Pelagia colorata has been changed to Chrysaora colorata by Lisa Gershwin.

p. 69. Photo 124 is Janthina prolongata rather than J. janthina. Roger Seapy has been looking at west coast Janthina specimens and concludes that our photo best matches J. prolongata (by e-mail 8.28.00).

p. 70, Photo 125. The Atlanta species illustrated is Atlanta californiensis . (Thanks to Roger Seapy.)

pp. 70, 100, 103, 105. Carinaria cristata and Carinaria cristata forma japonica are probably better interpreted on the west coast as being the species Carinaria japonica Okutani, 1957. (Thanks to Roger Seapy.)

p. 71, Photo 128. The Pterotrachea species illustrated is Pterotrachea coronata . (Thanks to Roger Seapy.)

p. 73. Note thatClio pyramidata shells do not typically have hydroids growing on them, although such hydroids are frequently seen on Clio recurva and Clio cuspidata . (Thanks to Carol Lalli.)

p. 74, Photo 134; p. 104. The species we labelled as Corolla calceola is actually Corolla spectabilis Dall, 1871. We missed a recent paper revising this genus by J. Rampal (Beaufortia, Aug. 1996), who points out the differences between these two species - C. spectabilis has 12 mucus glands in a row, while C. calceola has 18. Only C. spectabilis seems to occur in the east Pacific. (Thanks to Carol Lalli.)

p. 75, Photo 137. The pteropod that we labelled as Crucibranchaea macrochira is not that species, but is probably a Pneumoderma sp. (Thanks to Carol Lalli.)

p. 81. Pegea confoederata and Pegea socia. Note that while P. confoederata is pictured on p. 81, P. socia is pictured on the book cover.


Mills, C. E. and J. T. Carlton, 1998. Rationale for a system of international reserves for the open ocean. Conservation Biology, 12: 244-247.

On page 245 of this paper we mistakenly stated that "internationally sanctioned regulations permit the release of nonbiodegradable plastic wastes in waters 50 miles from continental margins (UNIMO, 1978)." In fact, disposal of plastic is prohibited everywhere in the oceans, and our statement should have read that regulations permit the release of paper, rags, glass, crockery, metal, food, and dunnage (non-plastic lining and packing materials that float) outside 25 miles from land.


Mills, C.E. and F. Sommer, 1995. Invertebrate introductions in marine habitats: two species of hydromedusae (Cnidaria) native to the Black Sea, Maeotias inexspectata and Blackfordia virginica, invade San Francisco Bay. Marine Biology, 122: 279-288.

The more we (Claudia Mills and John Rees) look at Maeotias and Blackfordia in tributaries to San Francisco Bay, the more things we find wrong with this otherwise fascinating paper! Corrections have now been accumulated and are published in a special volume of hydrozoan papers in Scientia Marina as: Mills, C.E. and J.T. Rees, 2000. New observations and corrections concerning the trio of invasive hydromedusae Maeotias marginata (=M. inexpectata), Blackfordia virginica, and Moerisia sp. in the San Francisco Estuary. Scientia Marina, 64 (Suppl. 1): in press.

The changes are summarized below:

Somehow, I managed not to see statocysts around the bell margin of Maeotias inexspectata (see p. 281) by the time this paper was published. My most careful examinations were of formalin-preserved specimens, in which the otoliths dissolve, rendering marginal statocysts very difficult to see - maybe that is how I missed them. Further observation of living specimens in August 1995 showed unquestionably that Maeotias does indeed have numerous marginal statocysts.

The presence of marginal statocysts puts into question placement of Maeotias within the Anthomedusae. As there are exceptions to many of the morphological characteristics that are grouped together to put hydromedusae into families and classes, I am not all that dismayed by an Anthomedusa having statocysts, but the Limnomedusae may at this point be a more appropriate location for Maeotias until more is known. On the other hand, recent unpublished molecular data of others indicates that the Limnomedusae belong somewhere within the Anthomedusae anyway. Molecular profiling of Maeotias would help answer the question of which group Maeotias is best placed within, and may occur within the next year or so.

In September 1997, Maeotias medusae were found in another low-salinity location in San Francisco Bay, along with a yet-unidentified species of Moerisia (another alien hydromedusa of Sarmatic origin!). Relationships between the two genera and their taxonomic positions (both have been moved from the Limnomedusae to the Anthomedusae) are presently under study by John Rees and Lisa Gershwin.

We found Blackfordia polyps in the field during the September 1997 collections, densely covering living barnacle shells in the Petaluma River. We also found polyps similar to those described in this paper as Maeotias. It has been brought to our attention that these polyps are likely to be those of Moerisia rather than Maeotias. More lab and field work needs to be done to elucidate differences between the polyps of these 2 species and to determine for certain whose polyp we described in this paper.

New field and lab work done in September 1998 by John Rees revealed 2 startling things. The first female Maeotias were found (!) and fertilized eggs developed into tiny polyps that seem very different than those we described, making those described in this paper even more likely to have been the polyps of Moerisia sp.


Mills, C.E. 1987. Revised classification of the genus Euplokamis Chun, 1880 (Ctenophora: Cydippida: Euplokamidae n. fam.), with a description of the new species Euplokamis dunlapae. Canadian Journal of Zoology, 65: 2661-2668.

The known problems with this paper all occur on p. 2667.
In the Key to Species of Euplokamis, a typo was made early on in my notes on the size of Euplokamis stationis, which can reach 2.5 cm or 25 mm in length, not 2.5 mm in length.
One ramification of this is that in couplet 2a, the second phrase referring to size should be deleted.

The Key to Species of Euplokamis includes 5 species, (E. brunnea having been removed in the Note added in Proof mentioned at the bottom of page 2667, back to Pleurobrachia brunnea based on my own observations in August 1987 in the Atlantic Gulf Stream). I am now tempted also to remove E. octoptera (previously Beroe octoptera of Mertens, 1833). In preparing for a trip to the Bering Sea in September 1997, I looked again at Mertens' work, and consulted with Richard Harbison; both of us believe that Beroe octoptera may very well be a synonym for Mertensia ovum. Unfortunately I did not see any ctenophores on that trip, which had the use of an ROV for 18 "dives" over 10 days off the Pribilof Islands, but whose vision was decidedly obscured by an unusual coccolithophore bloom, so no new observations are available to further clarify this issue.

Since having written this paper, I have personally seen Euplokamis stationis. It was quite common in the Alborán Sea off Morocco in April 1991 between 183 and 729 m deep.

I have also now observed and collected Euplokamis dunlapae in the Atlantic Ocean, while using a manned submersible in the Gulf of Maine in September 1993 between 165 and 245 m deep.

** This page is maintained by C. E. Mills; established March 1998; last updated 25 February 2003 **

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