538 PBOr. TV. A. HEEDMAK S BEVISED 



{Onlv the branchial siphon eohinated. M. echinosiphonica, Lac.-Duth. 

 [(N.W. Eur.) 

 Both siphons echinated M. nuda,Wa.gn. (Arct.) 



nj- f Body globular, not attached M. cmpiformis, Herdni. (N.W. E.) 



^^iBodj attached 26 



nn r With a short peduncle M.pedunciolata,'KQrAm.{k.A.vct.) 



^"\ With no peduncle 27 



{Attached by a wide area partly on left side. 

 _M. citrina, A. & H. (N.W. Eur.) 

 Attached by a narrow area at posterior end. 

 M. Helleri, t. Dr. (Med.) 



(Aperture of dorsal tubercle turned to right side ; anus with entire 

 free edge 28 

 Aperture of dorsal tubercle turned posteriorly ; anal margin entire, 

 but adhering M.septeiitrionalis,Trdust. (? Arct.) 



(Six series of conical papillae on the test rouad the branchial aperture. 

 M. nana, Kupff. (N.W, Eur.) 

 No such papillae present ; siphons long. [Eur.) 



Sf. solenota, Lac.-Duth. (N.W. 



„, J No sand &c. on the test M. gregaria, Less. (Mag.) 



^^ [Test sandy 29 



{Mantle thick and opaque, with muscles forming a close network. 

 M. horrida, Herdm. (Mag.) 

 Mantle thin, transparent, with the usual Molgulid musculature 30 



(Inferior margin of anus adhering 31 

 Margin of anus entire, free ; large genital papillfe on each side of 

 rectum ilf.^Zem, Lac.-Duth. (N.W. Eur.) 



r Stigmata small and short ; anus bilabiate. 

 31s M. groenlandica, Ti-aust. (N. Atl.) 



[ Stigmata Tery long; anus rounded.,. M.' roscovita, Lac.-Duth. (N.W. 



[Eur.) 



,Mal.) 

 on a fold M. Martensii, Traust. (Ind. 0.) 



,g r4 int. long, bars on a fold M.Forbesi, Herdm. (Austr.,Mal.) 



\ 5 or 6 int. long, bars ---- — 



Molgula boreas, Traustedt (Arct. ?), appears to come in here 

 "beside M. Forhesi and M. Martensii, but I am unable to find a 

 description which will give differentiating characters. 



Etj&xkiopsis, Boule, 1885. 



Body ovoid, attached ; not incrusted with sand. 

 Test smooth, thick, with no hair-like processes. 

 Mantle thin; musculature weak, but both longitudinal and 



transverse. 



Branchial sac with 7 folds on each side. Stigmata curved, and 



coiled spirally in infundibula. 

 Tentacles compound. 

 Alimentary canal on the left side. 



