part 2 : ACL [SIX A a:s'D aclisoides. 69 



the typical A. pulclira, but they are much smaller and rather 

 more slender. At least eight and twenty Scottish specimens are 

 remarkable for having the protoconch intact, and some also exhibit 

 the characteristic sigmoidal lines of growth. 



Holotype. — Op. cit. pi. iii, tig. 2, In the Neilson Collection, 

 Koyal Scottish Museum, Edinburgh. 



Locality and horizon. — Kobroyston, Grlasgow, in the Upper 

 limestone Series. 



Unfortunately the finer specimen (fig. 1) from Swindridge Muir, 

 Ayrshire, also in the Upper Limestone Series, has perished by fire. 

 There are, however, numerous examples from this locality in the 

 Young, Xeilson, and my own collections. 



Specimens in Mr. J. Smith's collection from the Index Lime- 

 stone at Highfield, Dairy, and Dernshaw, Stewarton, have the 

 protoconch preserved, as well as those previouslv mentioned from 

 the last-named localitj'. 



AcLisiXA PULCHEA, var. INTERMEDIA Donald. 



Aclisina pulchra, var. intermedia Donald, 1898, op. cit. p. 53 & pi. iii, tigs. 5-5«, 



Ke marks. — Specimens previously referred to this variety from 

 Swindridge Muir are most probably A. costatula. 



Holotype. — Op. cit. pi. iii, figs. 5 & oa. Bennie Collection, 

 lioyal Scottish Museum, Edinburgh. 



Locality and h o r i z o n. — Law, Dairy ( Ayrshire) , in the Lower 

 Limestone Series. 



Aclisina venusta, sp. nov. (PI. V, figs. 3 r/ & 3 h.) 



Diagnosis. — Shell elongated, conical, composed of more than 

 seven whorls. Whorls convex, ornamented on the lower part by 

 four threads, the two upper of which are the strongest and farthest 

 apart; midway between these and the suture are two finer ones, and 

 on the body-whorl there are two additional fine threads below. 

 Sutures deep. Base convex, slightly produced. Inner lip refiected. 

 Columella nearly straight. 



Remarks. — From A. iniJchra this species maybe distinguished 

 by being more slender and having more regularly convex whorls. 

 It is most like the variety intermedia, but is of much gi;eater size, 

 and has also two fine threads on the upper part of the whorl. We 

 have, however, only one example of each of these forms ; it is 

 therefore possible that the discovery of intermediate links might 

 prove them to be the extremes of a single species or variety. 



Holotype. — PLY, figs. 3^ & 3/;, Bennie Collection, Royal 

 Scottish Museum, Edinburgh. 



Dimensions. — Length = S millimetres ; width = 3 mm. 



Locality and horizon. — Law, Dairy, in the Lower Limestone 

 Series. 



