new Gastropoda from the Persian Gulf, &e. 299 
globosi, duobus ultimis hexagonis, utrinque tri-carinatis, squamo- 
sis, carinis sex minute et formosissime echinulatis, undique 
longitudinaliter tenuiliratis, liris arctis, inconspicuis; apertura 
sex-angulata, intus alba, labro tenui. 
Alt. 2, diam. 5 mm. 
Hab. Gulf of Oman, lat. 24° 58’ N., long. 56° 54’ E., 
156 fathoms. 
A very extraordinary, though minute, species, the chief 
peculiarities consisting in the completely evolute hexagonal 
whorls, the keels being most beautifully echinulate, the 
spaces also between the carine are longitudinally lirate. 
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. zanclea, 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. pernam- 
bucensis (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 Omalazxis, Desh., 
1832 * (atterwards altered to Homalawis), 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 
Homalazis must therefore stand, in spite of its disadvan- 
tageous origin. 
Hlomalaxis rotula-catharinea, sp.n. (PI. XXI. fig. 3.) 
H. testa minuta, depresso-discoidali, alba, delicata, semievoluta ; 
anfractibus quatuor, rectis, utrinque bicarinatis, apicali immerso, 
simplici, antepenultimo levi, parum nitente, penultimo, simul 
ac ultimo, pulcherrime sculpturatis, evolutis, utrinque bicarinatis, 
carinis—preecipue externis—apud margines minute echinato- 
erenulatis; 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 /Z. zan- 
clea, Phil., but more delicate in every detail. JH. disjuncta, 
Lam., a tertiary fossil from Grignon, is very much larger 
* Deshayes, Encyclop. Méthod. vol. iii. p. 659, 
