ECTEINASCIDIA AND THE CLAVELINHLE. 157 



central mass, while about sixty spermatic vesicles com- 

 pose the crescentic testis outside. The ducts from the 

 spermatic vesicles unite on the anterior edge of the ovary 

 to form the vas deferens (PI. VII, fig. 7) which, along with 

 the oviduct, leaves the genital mass between the horns of 

 the crescent and curves anteriorly to cross the intestine 

 where it joins the rectum. The genital ducts then course 

 along the ventral edge of the rectum to their termination 

 near the anus. 



This species, from Alexandria Harbour, resembles the 

 preceding one closely in external appearance and in the 

 condition of the tentacles. They differ, however, in the 

 size of the transverse vessels of the branchial sac, the 

 condition of the connecting ducts, the dorsal languets, and 

 the course of the alimentary canal and genital ducts. The 

 connecting ducts and dorsal languets differ from those of 

 all the other members of the genus Ecteinasciclia in the 

 restricted sense, and resemble those of Bhopalopsis crassa 

 and Bh. fusca, but in other points the present species is 

 much nearer to E. turbinata, E. cliaphanis and E. 

 thurstoni. 



It is curious that these four species, which are so very 

 much alike in external appearance, but differ from one 

 another in details of internal structure, should be known 

 only from such very widely separated localities, viz. — 



Ecteinasciclia turbinata, Herdm., Bermuda, N. Atlantic. 



E. cliaphanis, Sluiter, from Billiton, Malay Archipelago. 



E. thurstoni, Herdm., from Gulf of Manaar, India. 



E. moorei, Herdm., from Alexandria, Mediterranean. 



Lesueur's Asciclia claviformis, from the Bay of St. 

 Vincent, West Indies, is evidently also an Ecteinasciclia, 

 but as the brief description* deals only with the external 



* Journ. Acad. Nat. Sc, Philadelphia, April, 1823, vol. iii, p. 5. 



