NOTE ON ANIMAL DISTRIBUTION FOLLOWING A 



HARD WINTER. 



W. C. ALLEE. 

 LAKE FOREST COLLEGE. 



For the past six summers I have been studying the distribution 

 of littoral invertebrates near Woods Hole, Mass., in connection 

 with a teaching appointment in the invertebrate course in the 

 Marine Biological Laboratory. The work has been largely 

 done in connection with the class trips which give a good oppor- 

 tunity for general collecting in that each of the six or seven 

 instructors has from six to eight students working with him in 

 the field. As a result of the class collecting during this period, 

 there are over 190 species of invertebrates listed in the class 

 catalogue that have been taken alive on student excursions. 



Something of the thoroughness of the collecting may be seen 

 from the fact that this work has added two new species to the 

 faunal catalogue of this well-studied region: In 1915 Dr. T. S. 

 Painter took a living specimen of Area ponder osa (Say) in dredg- 

 ing off Naushon in Vineyard Sound. The animal was taken on 

 the sand dollar grounds off Tarpaulin Cove in about six fathoms 

 of water. Regarding this species the Biological Survey 1 says: 

 ;< Verrill has expressed doubts as to whether Area ponder 'osa lives 

 in this region since no living specimen has been taken north of 

 Cape Hatteras. Mr. G. M. Gray likewise reports that he has 

 never taken this species alive. Dr. Dall informs us, however, 

 that the National Museum contains a fresh valve, retaining the 

 epidermis, taken in Vineyard Sound in 1870; and Mr. C. M. 

 Johnson reports that he has found more than one shell of this 

 species still bearing evident traces of the hinge ligament and 

 epidermis, on a beach near Chatham Light." The extensive 

 dredgings of the survey yielded only a few shells. The range is 

 usually given as extending from Provincetown to Yucatan. 



1 Biological Survey of the Waters of Woods Hole and Vicinity by Francis B. 

 Sumner, Raymond C. Osborn, and Leon J. Cole. Bull. Bureau of Fisheries, Vol. 

 31. Two parts. 



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