462 THE VOYAGE OF H.M.S. CHALLENGER. 



The nomenclature in this and some of the closely connected genera is very confused. Reeve 

 says this species is slightly wrinkled — the Challenger specimens are more so than is usual, and very 

 much resemble Mitrularia tortilis, Reeve, but that species has not the fine, twisted, and persistent apex 

 which is present here — the longitudinal striae in it are coarse, and the locality forbids the union of 

 the Challenger specimens with it, for it is a native of the Galapagos. I have with much hesitation 

 united to this species the specimens from Station 113a; in them the embryonic apex is more 

 appressed than it is in those from the other two stations, but the general texture and sculpture are very 

 much alike. As usual in the case of all critical species, whether his own or of other people, Reeve 

 gives no help, and Gray (Joe. eit.) seems to have made his Calyptra Uctum-sincnsc a sort of refuge for 

 destitute species from every quarter. Eighteen species are sheltered under it — one of these, Calyptra 

 deprcssa, Adams and Reeve, having been already classed as a synonym of Calyptra adamsii, Reeve. 

 After this Dr Gray adds, " I am by no means certain that the six species here distinguished " (con- 

 stituting the whole Ust of admitted species) " are distinct," and he concludes, " They all seem to live 

 together at the Philippine Islands," which they certainly do not. Obviously, therefore, the whole 

 group requires careful examination and criticism. In the meantime,'guess-work alone being possible, 

 I content myself with putting the specimens I have to deal with in the group nearest in form and in 

 dwelling-place. I ought perhaps to add that somewhat similarly, as regards the name of the genus, 

 I have been glad to accept, not what is or might be best, but what seemed least open to objection. 



Family Phorid^e, Gray, 1840. 

 Genus Xenophora, Fischer von Waldkeim, 1807. 

 Onustus was a mere museum name of Humphreys. Phorus of Montfort dates from 1810. 



Species. 



1. Xenophora caribma, Petit. 3. Xenophora helvacea, Philippi. 



2. Xenophora corrugata (Reeve). 4. Xenophora pallidida (Reeve). 



5. Xenophora solarioldes (Reeve). 



1. Xenophora caribcea, Petit. 



Xenophora caribcea, Petit de la Saussaye, Journ. de conch., 1857, voL v. p. 248, pL x. figs. 1, 2. 

 ,, „ Fischer, Cat. coq. de Guadaloupe, Revue coloniale, p. 12 (separate impression). 



„ „ Fischer, Kiener's Iconog. (Trochus), p. 429, sp. 2, pi. Ixv. fig. 1. 



Station 122. September 10, 1873. Lat. 9° 5' S., long. 34° 50' W. Off Pernambuco. 

 350 fathoms. Red mud. 



Habitat. — West Indies. 



Fischer, in his Guadaloupe Catalogue (loc. cit. supra) remarks of this species that it " provient de la 

 cote de Marie-Galaute quartier du vieux fort Saint Louis.' M. de Villepin en a trouve 11 exemplaires 

 sur des nasses de pecheurs, mouillees a de grandes profondeurs." In general aspect, though much 



