116 Proceedings of the Royal Irish Academy. 



B. Mesenteries. — On comparing sections of B. tuediae with the sections of 

 my " Terra Xova " lo - I rind that the mesenteries might be described 



in almost the same terms for both : but the processes of the muscle-pennon 

 are rather more numerous, more crowded, finer, and some of them rather 

 differently branched, in tuedieu than in longicornis\ and the parietobasilar 

 muscle of the former is rather the stronger. The nature of a typical tued 

 mesentery is shown in l'l. XX. fig. 4. In different mesenteries the parieto- 

 basilar muscle varies, usually forming a distinct free fold. Sometimes one 

 partner in a mi 1 pair is considerably larger than the other. 



/ —The tentacular longitudinal musculature of tuedia* l'l. XX. 



tially different from that of Ion 



One qnesl mains: Is the European B. identical or not with 



the American Bolocera described by Verrill as B. tuediae ? I cannot give a 

 definite answer. But Prof. McMurricb has favoured me with a sketch of the 

 sphincter of the A in form, and though on the whole quite like the 



European, it has more of an upper " twig" than my specimens show. Sections 

 of a • imen includi entatives of al least 4, possibly 5, 



cycles of mes - oly on those of the last cycle but one. 



Further research with more material is really required before we can 

 state to whal the sphincter, for instance, may vary in "lie and the 



same species. 



5. Bolocera longicornis Carlgren. (PL XX, tig. 7.) 



I. SB. 172 1004. 54 miles W. by X. \ X. Xly. of Tearaght 



Light Lat. N. 52 % : Long. W. 12 8'. 454 fathoms. Tow-net on trawl. 

 1 youj _ oen. 



- 81 27. M > • 1906 60 miles W. | N. of Tearaght Light. Lat. 



N. 51 46'. 12° Lthoms. Trawl. 1 specimen. 



SB. 506. Sept 12, 1 og. W. 11 19'. 661- 



os. TrawL 1 specimen. 



4. SB. 1242. Aug. 14, 1911. 56 miles W. i S. of Great Skellig. Lat. X. 



51 . _. \\". i ; 55'. [ specimen, with 1 A 390 fathoms. 



•vl. 



- " miles W. \ N.of Great Skellig. Lat. X. 



11 51'. 479 " rrawl. 2 specimens. 



The next •"■ i :t down as /;. | ?). 



5B.171. • 104. 48 miles N. W. by W. f W. of Tearaght Light. 



Lit. X. :■_■ 7'; Long. W. 11 58'. 337 fathoms. Trawl. 22 specimens, all 



I, with practically no tent irly all turned in- 



out. 



