166 PERCY SLADEN TRUST EXPEDITION 



2. Limacina trochiformis (d'Orbigny). 



Stat. P. (3), Ohagos Archipelago; n (1), Saya de Mai ha Bank; dd (I), Amirante 

 Group. 



3. Limacina bulimoides (d'Orbigny). 

 Stat. P (13), Ghagos Archipelago. 



Peraclis* Forbes. 



4. Peraclis reticulata (d'Orbigny). 

 Stat, u (l), Farquhar. 



Cavoliniidse. 



Creseis. 



5. Creseis virgula Rang. 



Stat. A (1), F (2), N. of Chagos Archipelago; d (1), Mauritius; e (1), Mauritius — 

 Cargados Carajos ; dd (13), nn (1), Amirante Group. 



6. Creseis acicula Rang. 



Stat. P (1), Chagos Archipelago ; u (3), Farquhar; x (3), Providence ; kk (6), nn (4), 

 Amirante Group. 



Styliola Lesueur. 



7. Styliola svhula (Quoy et Gaimard). 



Stat, e (I), Mauritius; n (l), N. of N. Saya de Malha Bank. 



Hyalocylix Fol. 



8. Hyalocylix striata (Rang). 



Stat. A (1), B (2), N. of Chagos Archipelago; H (l), L (4), Chagos Archipelago; 

 e (1), Mauritius— Cargados Carajos; n (8), N. of N. Saya de Malha Bank; v (l), 

 Farquhar ; kk (4), mm (1), Amirante Group. 



Cuvierina Boas. 



9. Cuvierina columnella (Rang). 



Stat. N (2), Chagos Archipelago; mm (1), nn (1), Amirante Group. 



* With regard to the recent paper of Meisenheimer (Die Pteropoden der deutschen Siidpolar- Expedition t 

 1901 — 1903, 1906) in which a chapter occurs on the genus Peraclis, I am doubtful about the specific 

 distinctness of his species P. apicifulva and another form, described almost simultaneously, by Pelseneer, 

 P. brevispira (Biscayan Plankton collected during a cruise of H.M.S. "Research," 1900, Part VII., Mollusca 

 (excluding Cephalopoda), Trans. Linn. Soc. London, vol. x. Part 5, February 1906). The general shape 

 of the shell is somewhat the same, differing only in the fact that in P. apicifulva there are 4 coils, 

 whereas in Pelseneer's species there are only 2£. The opercula agree closely, especially in the striated 

 portions around the central coils of the nucleus. The small rim-like elevations, perpendicular to the 

 suture on the last whorl, in P. apicifulva occur also in P. brevispira in the form of "petites lamelles 

 rayonnantes, surtout visibles au dernier tour." Finally the sculpture seems to be alike in both species. 



