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SCIENCE 



[N. S. Vol. LIII. No. 1376 



at the Pribilof Islands in the Bering Sea, and 

 the presumption is that the bryozoa are from 

 the same locality. The food records are as 

 follows : 



Crisia sp., from stomachs of the king eider 

 and of two Pacific eiders, St. Paul I., 

 Alaska, January 29 and 30, 1918. 



Menipea pribilofi Eobertson, from stomach of 



king eider, St. George I., Alaska, January 



30, 1918. 

 Myriozoum suhgracile d'Orbigny, from stomach 



of king eider, St. George I., Alaska, May 3, 



1917. 

 Cellepora surcularis Packard, from stomachs 



of the Pacific eider, St. Paul I., Alaska, 



Mch. 21, 1915, and from the king eider, St. 



Paul I., Alaska, December 13, 1914 and 



January 29, 1918. 



The amount of material in each case was 

 small. The Crisia colonies were broken 

 scraps and undeterminable as to species be- 

 cause of the lack of ovicells, though the gen- 

 eral appearance was that of the common C. 

 denticulaia Lamarck. Myriozoum suhgracile 

 was represented by a branched portion 9 mm. 

 long by 3 mm. thick, and Cellepora surcularis 

 by irregular nodules 4 to 12 mm. in gi-eatest 

 diameter. 



In all cases the animal matter seemed to 

 have been digested out, leaving only the 

 chitinous or calcareous matter of the ectocyst. 

 Aside from the fact that they were consider- 

 ably broken up, the specimens were in good 

 condition for study, being as clean as though 

 they had been treated with Javelle water. As 

 Dr. Nelson suggests in a letter, it is probable 

 that the ducks ate the Crisia and Menipea 

 incidentally with other food, as these small 

 branched species often grow attached to other 

 organisms. The Myriozoum and Cellepora be- 

 ing nodular, may have been swallowed in lieu 

 of pebbles. 



In general the bryozoa muSt afford com- 

 paratively little nutriment, as the indigestible 

 portion is so large, yet an animal pressed for 

 food might be able to eke out an existence on 

 them. 



Certain fishes that habitually browse around 

 ledges, rocks, wharves, etc., and which have 

 teeth adapted for cutting off and crushing the 

 shells of their prey, are known to include 

 Bryozoa in their diet with some regularity. 

 Thus, the cunner, Tautogolabrus adspersus, 

 and the blackfish or tautog, Tautoga onitis, 

 feed on bryozoa along with other hardshelled 

 organisms. (See Sumner, Osburn and Cole, 

 " Biological Survey of the Waters of Woods 

 Hole and Vicinity," Bull. U. S. Bureau of 

 Fisheries, Vol XXXL, Part 2, 1911.) The 

 kingfish, Menticirrhus saxatilis, also has been 

 known to feed on bryozoa. The writer has 

 observed Bugula turrita Desor and Lepralia 

 yallasiana Moll among the stomach contents 

 of the puffer or swellfish, Spheroides macu- 

 latus. On one occasion a couple of young 

 puffers were placed over night in a finger 

 bowl containing some colonies of the Endo- 

 proct, Barentsia major Hincks, and the next 

 morning it was discovered that the puffers 

 had returned my kindness in keeping them 

 alive a few hours longer by eating the heads 

 off of the most of the Barentsia. I have seen 

 a considerable mass of Bugula turrita taken 

 from the stomach of a smooth dogfish, 

 Mustelus canis, and on several occasions have 

 had referred to me for identification, nodules 

 of Smittina trispinosa nitida Verrill and 

 Schizoporella unicornis Johnston, from the 

 stomachs of sharks. In one case the colony 

 was half as large as my fist. 



Bryozoa often grow in the greatest profu- 

 sion, covering piles, rocks, shells, seaweed, 

 etc., with growths so dense that they may 

 entirely obscure the objects to which they are 

 attached. At Woods Hole, Mass., during the 

 summer of 1919, observations were made on 

 Bugula turrita, growing on the rock wall of 

 the Bureau of Fisheries dock, and on Lepralia 

 pallasiana, encrusting the piles and timbers 

 under the Coast Guard dock. Though in both 

 cases the substratum was practically covered 

 by the bryozoa and there were many other 

 animals present, very few of the colonies 

 showed injury of any sort. In nearly every 

 case the colony form was perfect. It has been 

 my experience in many years of dredging that 



