MOORE ABXOKMAL SECONDARY DEPOSITS. 553 



strise. Base of the shell and umbilicus deeply excavated and sur- 

 rounded by very distinct encircling striae. 



From the Brocastle Liassic conglomerate, where it is rare. It is 

 named after my friend Dr. Lycett, to whose researches we are in- 

 debted for the separation of this genus from the Pleurotomarice. 



57. Trochfs apicalis, spec. nov. PI. XVI. figs. 20, 21, 22. 



Shell pyramidal, regularly tapering ; apex acute ; volutions eight, 

 narrow, very closely encircling ; base of the volutions carinated ; 

 suture almost obsolete ; surface smooth. The bottom of the shell 

 is smooth, discoidal, rather concave ; aperture very narrow, trans- 

 verse ; outer lip curved and folding round a truncated columella, 

 which terminates in a central boss. 



Of this species, which does not appear to attain a large size, I 

 possess four examples from the Brocastle Liassic conglomerate. 



58. TROcnrs gradattjs, spec. nov. PI. XYII. fig. 5. 



Shell conical, thick ; apex rather obtuse ; volutions 4-5, shghtly 

 convex, and separated by a very slight concave suture ; whorls very 

 slowly increasing ; surface smooth. 



At first this shell looks not unlike the T. aciculvs, Horn., often 

 found on the Hierlatz ; but it does not possess the distinct encircling 

 suture between the whorls of that species, which also possesses a 

 more acute spire. 



This shell is not uncommon, as portions of several are to be de- 

 tected, partly concealed by the matrix, in the block from the Liassic 

 infilling in the Carboniferous-limestone quarry at Holwell. 



59. Trochus Deslongchampsii, spec. nov. PI. XYI. fig. 15. 



Shell turbinated, trochiform ; apex subacute ; whorls 5, step-like, 

 the upper flattened, the surface of the body- whorl more angulated, 

 and surrounded on its margin by two very produced rounded carina?, 

 which are slightly nodulated towards the aperture, between which 

 there is a very distinct and deep transverse canal ; aperture sub- 

 quadrate. The surface of the shell possesses very close angulated 

 striae. 



The species is rare. I possess three examples, all of which are 

 from the Brocastle Liassic conglomerate. It is named after my 

 friend M. Deslongchamps, whose investigations have added much to 

 our knowledge of Liassic Gasteropoda. 



60. TROcnrs Langanensis, spec. nov. PI. XYI. fig. 18. 



Shell rather small, discoidal, depressed ; apex rather acute ; volu- 

 tions 4-5, rather convex. 



On the angulated margin of the shell are two depressed transverse 

 carinae, between which is a flattened or slightly concave area. The 

 volutions have very fine concentric or transverse striae. Aperture 

 subquadi'ate. 



