598 MR. G. B. SOWERBY ON NEW SPECIES OF SHELLS. [Nov. 3, 



its favour is that the combination of anatomical characters is exactly 

 the same in all its genera, which have a very scattered distribution. 

 It will be noticed that no Parrots with normal carotids occur in 

 the New World ; and, as far as I know, none but members of that 

 group have red beaks. 



P.S. (December 8th, 1874).— On the 25th of last month, from the 

 death of one of the specimens of Stringops habroptilus, recently pur- 

 chased by the Society, I have had an opportunity of dissecting a 

 third individual of the species. In it the ambiens muscle is complete, 

 of fair size, at the same time that it crosses the knee as in Psit- 

 tacus. This makes me feel more convinced that the arrangement 

 indicated by the dotted portions of the diagram plates accompanying 

 this communication is the correct one, and that the main stem has 

 given rise to three instead of two branches — the Stringopinse being 

 the nearest representatives of the ancestral form, some of its members 

 (Geopsittacus, Melopsittacus, Euphema, and Cyanorhamphus) having 

 quite recently lost, whilst Stringops itself is just now on the point of 

 losing the ambiens muscle. It is, however, quite possible, if external 

 resemblances and geographical distribution are left out of considera- 

 tion, that Stringops must stand as the sole representative of the 

 Stringopinse, thus conforming with generally received ideas ; and 

 that Geopsittacus, together with Melopsittacus, Euphema, and Cya- 

 norhamphus, must be placed with Agapornis as part of the family 

 Agapornithinae, in which the formula is 2,—, — , + . The close ex- 

 ternal resemblance between Stringops and Geopsittacus nevertheless 

 makes me indisposed to adopt this view. 



7. Descriptions of five new Species of Shells. 



By G. B. Sowerby, Jun. 



[Received September 15, 1874.] 



(Plate LXXII.) 



1. Triton (Epidromus) comptus, sp. nov. (Plate LXXII. 

 figs. 5, 5 a.) 



T. testa oblongo-turrita, rufo-fusca, castaneo maculata, undique 

 creberrime decussate lirata, liris eximie granulosis, interstitiis 

 transversim striatis ; anfractibus rotundatis, maculis angustis 

 oblongis transversim balteatis ; varicibus paucis, rotundatis, 

 castaneo grandimaculatis ; apertura subexpansa, labio externa 

 reflexo, Icevi, ad marginem lineis castaneis minutis notatis ; 

 lamina columellari Icevi, pellucida, polita ; canali brevissimo 

 recurvo: long. 54, lat. 20; apert. long. 20, lat. 10 mill. 

 Shell of the usual general form of an Epidromus (Klein) as sepa- 

 rated from the genus Triton (Lamarck), reddish-brown colour, 

 blotched and spotted with dark chestnut-brown, closely and exqui- 

 sitely cancellated and granulated ; whorls rounded, belted with narrow 

 oblong spots ; varices few, rounded, with large chestnut blotches ; 

 aperture rather expanded ; outer lip reflexed, smooth, with small 



