ASCIDIANS COLLECTED IN PUGET SOUND. 



249 



I have already in the previous paper (this vol., p. 89) 

 drawn attention to the resemblance between the marine 

 fauna of Puget Sound and that of North- West Europe — 

 say the British and Scandinavian coasts. I think it may 

 with truth be said that all the Ascidians I obtained in 

 this arm of the North Pacific are closely related to 

 familiar species on our own North Atlantic coasts. I can 

 draw up parallel series* as follows : — 



Puc-et Sound. 

 Chelyosoma producttcm, St. 



Corella willmeriana; n. sp. 



Ascidiella incrustans, n. sp. 

 Ascidiella griffini, n. sp. 



Cynthia haustor, St. 

 Cynthia villosa, St. 

 Styela gibbsii, St. 

 Styela joannce, n. sp. 



Molgula pugetiensis, n. sp. 



Noeth Atlantic. 



Chelyosoma macleayanum, 



Brod. & Sower. 

 Corella parallelogramma, 



0. P. Mull. 

 Ascidiella (?) depressa, Aid. 

 Ascidiella aspersa (var. 



pustidosa), O.P.M. 

 Cynthia squamulosa, Aid. 

 Cynthia echinata, L. 

 Styela rustica, L. 

 Polycarpa (? Styela) fin- 



markiensis, Kiaer. 

 Molgula septen trionalis, T. 



This, taken along with the similarity between the two 

 faunas shown in other groups, suggests the possibility 

 that there is a common northern circum-polar marine 

 fauna which sends extensions southwards on the western 

 coasts of Europe and America, t 



I notice, with much interest, in the current number of 

 "Science" (No. 172, p. 540) that at the meeting of the 

 New York Academy of Sciences held on March 14th, 



* I believe Mr. Walker will show similar series for the Crustacea. 



t See also Mr, Walker's remarks in regard to Crustacea, this vol., p. 270.. 



