BIOLOGICAL SURVEY OF WOODS HOLE AND VICINITY. 1 57 



Verrill and Smith (1873) listed 18 determined species of tunicates for local waters, 

 together with two which were not definitely recorded for the region, and five others 

 which were not specifically determined. A number of these ascidians had been recently 

 described by Verrill himself from specimens taken in the vicinity of Woods Hole. The 

 Lcptodinum luteolum of Verrill is not regarded by Dr. Van Name as specifically dis- 

 tinct from the L. alhidum of the same author, which, contrary to the belief of "Verrill, 

 does not appear to occur within the limits of our region. The "Ciona tenella" of 

 Stimpson and of Verrill is now regarded as identical with C. intestinalis (Linnaeus), 

 while the "Salpa caboti" of Desor, which appears in Verrill's list, is not beUeved to be 

 distinct from the Salpa democratica-mucronata of Forskal." 



Certain species listed by Verrill (Molgula papulosa, M. pellucida, M. producia, Eugyra 

 piliilaris, Cynthia cartiea, Glandula arenicola) have not been recorded for local waters by 

 any subsequent writers.'' On the other hand, one species new to science {Bostricho- 

 brmtclius molgidoides) was described by Metcalf from specimens taken within recent years 

 in Buzzards Bay. Another species {Didemnum lutarium Van Name) although abund- 

 ant and familiar locally, was only recently described for the first time. This species 

 had hitherto been confused with Verrill's Leptoclinum albidum { = luieolum), the true 

 home of which is north of Cape Cod. The survey has encountered a number of species 

 which have not previously been listed in any published report of the fauna of this region. 

 Such are Ascidia complanata, Eugyra glutinans, and Salpa zonaria-cordiforniis; also 

 (doubtfully determined) Molgula koreni, M. ciirina, and M. pannosa. 



Twenty-eight species of Tunicata are recorded by Whiteaves for eastern Canada; 

 36 species are comprised in the Plymouth Hst; 45(-f 14?) for the Irish Sea; and 75 for 

 the Gulf of Trieste. Ten of the Canadian species and 2 of the Plymouth species appear 

 to be common to our Woods Hole fauna. In considering any such comparisons, how- 

 ever, it must be borne in mind that practically no papers have been pubUshed during 

 the past 30 years which deal with the New England Tunicata. 



Only eight charts (190-197) have been presented as illustrating the distribution 

 of the bottom-dwelling ascidians of Vineyard Sound and Buzzards Bay. Of these, 

 seven are each for a single species, while another is based upon the records for two 

 species (Molgula arcnaia and Eugyra glutinans) concerning which some confusion exists 

 (see p. 156). 



Like most of the fixed organisms which have been discussed in the present report, 

 the ascidians are of far less frequent occurrence in Buzzards Bay than in Vineyard 

 Sound. Indeed, only two species, Molgida manhattensis and Didemnum lutarium, 

 occur with any frequency in the Buzzards Bay dredgings. The following figures permit 

 a comparison of the average number of species per dredge haul taken in the two bodies 

 of water: 



Vineyard Sound : 



Fish Ha wk i. 2 



Phalarope i. 6 



Buzzards Cay: 



Fish Hawk 4 



Phalarope -j 



a Ritter. 



*» These are all contained in the list of mol^lids having "very imperfect descriptions" in Herdman's " Revised Classification 

 of the Tunicata" (Joiirn. I,innaean Soc. vol. xxm. 1891, pp. 557-653). 



