REPORT UN THE LAMELLIBRANCHIATA. 271 



Family M Y t 1 1. 1 d .-e. 

 Subfamily Dreissenin.^. 



Sejitifc'i-, Recluz. 



Septifer h'docularis, (Liune). 



Mytilus hilocidaris, Linn6, Syst. Nat., ed. 12, p. 1156. 



Mytilus hilocidaris, Wood, Ind. Test., pi. xii. fig. 17. 



Mytilus nicoharicus, Chemnitz, Concli.-Cab., vol. viii. p. 155, pi. Ixxxii. figs. 736, a, h. 



Ticliogonia bilocularis, Kiister, Conch. -Cab., ed. 2, p. 10, pi. ii. figs. 11-17. 



Tichoijonia wiefjmanidi, Kiister, luc. cit, p. 11, pi. ii. iigs. 6-10. 



Tichogonia Jcraussii, Kiister, loc. cit., pi. vi. iigs. 1-6. 



Septifer bilocularis, Recluz, Rev. et Mag. Zool., 1848, p. 278. 



Septifei- hilocidaris, Recluz, Rev. et Mag. Zool., 1849, vol. i. p. 125. 



Septifer hilocuhiris, Martens, iloll. INlauritius, p. 318. 



Mytdus nicoharicus, Reeve, Conch. Icon., vol. x. pi. ix. fig. 42. 



Mytihis pdosiis (Recluz, MS.), Reeve, loc. cit., pi. viii. fig. 35. 



Septifer cuniingii, Eccluz, Rev. et Mag. Zool., 1849, vol. L p. 132. 



Mytilus cunnngianus, Reeve, loc. cit., pi. xi. fig. 52. 



Habitat. — Off Le\'nka, Fiji, in 12 fathoms. 



The small shells described by Recluz as Septifer cumingii should not, I think, be 

 separated from this species. They are said by Reeve (who wrongly quotes the species 

 both orthographically and as undescribed) to have come from Panama, and Recluz gives 

 their locality as " les cotes de I'ile Annaa (pres le detroit de Panama), dans Toc^an- 

 Pacifique." I have not been able to discover any island of that name near Panama, the 

 only Annaa Island with which I am acquainted being situated in the Low Archipelago, 

 east of Tahiti. 



Many shells were collected b)^ ]\'Ir. Cuming at the " Island of Annaa, Pacific Ocean/' 

 judging from Reeve's Conchologia Iconica, where it is very often mentioned. It therefore 

 seems to me probable that the Septifer cumingii was collected at the same island in 

 the Mid South Pacific and not in the Panama region. 



Some minute shells were identified with this species by Carpenter (Mazatlan Cat., 

 p. 120), and it is subsequently stated to be "common" at Cape St. Lucas, California 

 {vide Moll. West. North America, 1872, p. 106). 



After a careful comparison of the types of Septifer cumingii and Septifer pilosus 

 with specimens of Septifer bilocularis, I am unable to discover any sufficient grounds for 

 separating them sjjecifically. 



This species seems to be widely distributed throughout the Indian Ocean and in 

 many parts of the Pacific. 



