40 



Caz'oliftia gibbosa (Rang). 



1836. Hyalaea gibbosa Rang in: d'Orbignv, Voyage dans rAmtrique meridionale, vol. V, 



p. 95, pi. V, figs. 16—20. 

 1836. Hyalaea flava d'Orbigny, Ibid., p. 97, pi. V, figs. 21 — 25. 

 1850. Cavolina gibbosa Gray, Catalogue of the Mollusca in the Collection of the British 



Museum, prt. II, Pteropoda, p. 8. 

 1850. Cavolina jlava Gray, Ibid., p. 8. 

 18S0. Hyalaea gegenbaitri Pfefier, Die Pteropoden des Hamburger Museums, Abh. Naturw. 



Ver. Hamb. Bd. VII, p. 86, figs. 7— 7a. 

 1886. Cavolinia gibbosa Locard, Prodrome conchyliologie frangaise, p. 22. 



Empty shells: 



Stat. 45. 7° 24' S., ii8°i5'.2E. 2 spec. 



4 S., 1 19° 56'.? E. II spec. 



7 S., 123° i6'.5 E. 3 spec. 



S., i20°34'.5E. I spec. 



6 N., 1 19° 8'.5 E. 16 spec. 

 ,5 N., ii9°4o' E. 7 spec. 



N., 120° 21' E. I spec. 



N., 1 20° 37'. 5 E. 2 spec. 



.1 N., 1 20° 44' E. 6 spec. 



S., I28°37'.5 E. I spec. 



S., 122° 12' E. 6 spec. 



S., 121° 18' E. I spec. 



7 S., i20°45'.5 E. 4 spec. 

 .5 S., 120° 19'. 2 E. 4 spec. 



S., 1 24° 39' E. 2 spec. 

 Stat. 300. 10° 48'. 6 S., 1 23° 23'. I E. I spec. 



Only empty shells of this species have been found. 1 think that living animals rarely occur 

 in the tropics (see d'Orbigny ^), Boas -), Pelsexeer ^), Muxthe '), at least in the neighbourhood 

 of the equator. 



Several authors, among them Souleyet '") and Bexsox "), have deplorabh' confused the 

 forms Hyalaea gibbosa Rang (= Hyalaea Jlava d'Orbigny) and Hyalaea gibbosa d'Orbigny 

 (= Hyalaea gegenbaitri Pfeffer). Pfeffer ') has given an account of the different interpretations. 



The Siboga-specimens agree in man)- points with the form jiaz'a d'Orbigny. Very probably, 

 however, gradual transitions may be found to gibbosa d'Orbigny, and I can scarcely attach any 

 importance to the maintaining of the differences between these forms. 



Boas ^) described a variety from the Indian Ocean ; I have seen specimens from this 

 region (32° -S., 3i°E.) from the Leyden Museum, which agree with his figure, but the variety 

 was not found in the collection of the Sibogra. 



1) Voyage d. I'Amer. mer. vol. V, p. 96. 



2) Spolia atl. p. iii. 



3) Chall. Rep. LXV, p. 82—83. 



3) Pterop. i Ups. L'n. Zool. Mus., Kih. t. K. Svenska vet-akad. Handl., Bd. 13, afd. IV, u" 2, p. 



5) Voyage de la Bonite, vol. II, p. 145. 



6) .\nn. and. Mag. Nat. Hist., ser. Ill, 7, p. 23 — 24. 



7) Abh. Natuvw. Ver. Hamb., p. 87. 



8) I., s. c, pi. 6, fig. 99(7. 



