TAYLOR : VARIATION OF I.IMX.liA PERKGRA. 289 



lection, and therefore must not be understood to under- rate 

 the value or interest of specimens in the collections of my 

 friends. 



As the type of the species I propose to adopt the form 

 considered by Dr. Jeffreys as typical, and figured by him in Brit. 

 Conch., v., pi. 7, f. 3, which agrees with the types of many other 

 authors, and also fairly conforms with the figure given by 

 Draparnaud when separating from it his L. ovaia. The form, 

 therefore, understood by me to be typical L. fcregra Miill., and 

 figured here has the 



Shell obliquely-ovate, thin, moderately glossy, yellowish-liorn colour. 

 irregularly striate by the lines of growth, and closely and uiicrn- 

 scopically striate spirally, with a few indistinct spiral ridges, epidermis 

 rather thin, whorls 4|- to 5, convex, the 

 last occupying nearly the whole of the shell, 

 spire produced and pointed, suture raiher 

 deep, mouth large, ^ths of the total length, 

 oval and very little contracted by the 

 penultimate whorl, outer lip thin, inner 

 lip folded on the columella, forming a 

 slight umbilical cleft, fold rather prominent 

 and curved. — Total length, 187 mill., diam. 

 14^ mill. : length of aperture 14 mill., diam. S mill. 



The outlines given above are an exact representation of 

 shells collected at Ackholme, near Doncaster, in April, 1S83. 



Before commencing to describe and figure the various 

 varieties it will be well to remind the student that almost innu- 

 merable minor modifications or sub-variations of every variety 

 may and probably do exi.st, and that strictly characteristic speci- 

 mens, with all peculiarities exactly as in the original shells for 

 which the name was instituted, are often exceedingly rare. 



I have, therefore, endeavoured in compiling the descrip- 

 tions of the various varieties to give the essential feature and 

 to eliminate such details as appeared to me to be individual 

 peculiarities, which might or might not be present in specimens 

 otherwise possessing the primary characters. In illustration of 

 the necessity of this course I may point out that 1 )r. Jeffreys, 



