94 JOURNAL, BOMBAY NATURAL HISTORY SOCIETY, Vol, XVI. 



HOMALAXIS CORNU-AMMONIS, sp. n. (PI. B. fig. 4.) 

 H. testa minuta, alba, omnino evoluta, delicata, depressulo-discoidali ; anfrac- 

 tibus quatuor, quorum duo apicales connexi, vitrei, globosi, duobus ultimis 

 hexagonis, utrinque tri-carinatis, squamosis, carinis sex minute et formosissime 

 echinulatis, undique longitudinaliter tenuiliratis, liris arctis, inconspicuis ; 

 aperture sex-angulata, intus alba, labro tenui. 

 Alt. 2, diam. 5 mm. 

 Hab. Gulf of Oman, lat. 24° 58' N., long. 56° 54' E., 15G fathoms. 

 A very extraordinary, though minute, species, the chief peculiarities con- 

 sisting in the completely evolute hexagonal whorls, the keels being most 

 beautifully echinulate, the spaces also between the carinas are longitudinally 

 Urate. In form it is discoidally depressed, with two glassy globular apical 

 whorls. We cannot exactly follow the reasons which prompt Dr. Fischer 

 (Man. de Conch, p. 714) to propose a subgenus Pseudomalaxis for H. zancha 

 Phil., and consider all the true Homalaxis, Desh., tertiary fossils. In our 

 opinion both the species now described belong to the typical genus, and it 

 would be impossible to disassociate H. pernambucensis (Wats.), described as a 

 Bifrontia, from them. In the latter the last whorl is partly evolute. 



The Rev. R. Boog Watson (Report 'Challenger ' Exped. xv. p. 137) would 

 allow the barbarous term Omalaxis, Desh., 1832 s (afterwards altered to Ho- 

 malaxis), to lapse, it being derived from two languages, and institute Bifrontia, 

 also of Deshayes, 1833. But we fear that very many terms used in Zoology, 

 and accepted, are likewise of hybrid origin, and Homalaxis must therefore 

 stand, in spite of its disadvantageous origin. 



HOMALAXIS ROTULA-CATHARINEA sp. n. (PI. B. fig. 3.) 

 H. testa minuta, depresso-discoidali, alba, delicata, semievoluta ; anfractibus 

 quatuor, rectis, utrinque bicarinatis, apicali immerso, simplici, antepenultimo 

 leevi, parum nitente, penultimo, simul ac ultimo, pulcherrime sculpturatis, 

 evolutis, utrinque bicarinatis, carinis— prsecipue externis— apud margines mi- 

 nute echinato-crenulatis ; apertura quadrata, labro tenui, margine columellari 

 paullulum reflexo. 

 Alt. 1, diam. 3 mm. 



Hab. Gulf of Oman, lat. 24° 58' N., long 56° 54' E., 156 fathoms. 

 A most exquisite shell, in many points resembling H. zanclea, Phil., but 

 more delicate in every detail. H. disjuncta, Lam., a tertiary fossil from Grignon, 

 is very much larger indeed, but comes in the same category as our species, 

 which occurred frequently at the above locality. It bears, in miniature, an 

 almost exact resemblance to a catherine-wheel, hence the specific name. 



CERITHIUM VERECUNDUMf, sp. n. (PI. B. fig. 5.) 



C. testa parva, solidiuscula, eleganter fusiformi, attenuata, pallide straminea ; 



anfractibus decern, quorum apicales duo fusci, non hyalini, cseteris apud 



* Deshayes, Encyclop. Method, vol. iii. p. 659, 

 t Verecundus, modest. 



