142 REVIEW: RECENT WORKS ON SHELLS 
found. The synoptical tables of the differences between the s 
of the more difficult genera, and the carefully-accentuated g 
of technical terms, cannot but be of the- greatest service t 
- student, for whom the task of identifying any shell is facilitat 
the excellent plates which supplement the description of the 
species. The frontispiece, a reproduction of enlarged phe 
of those bugbears of the tyro, the Pisidia, merits specia 
In addition to the clear and accurate descriptions of the sh 
manual abounds in the practical information about the app 
and habits of the creatures themselves, which is born_ only of 
observation and extensive work in the field. 
ociety, steers a middle course between the ‘splitters’ an 
As each of the eighty-nine possible forms of plain banding in 
nemoralis and H. hortensis (page 70) may be associated ith 
six or seven different ground colours, and as shells of each 
may be dextral or sinistral, and vary in size, shape, and 
field for the enthusiastic variety-monger is still vast indeed, evel 
he ignores split or interrupted bands, and variation in the ©0! 
the lip. 
Mr. Carrington apparently attaches an exaggerated im| 
to the bands, as his list of possible combinations is entirely 
reference to the ground colour of the shells; and he errs 1 
that the type in each species may be of any colour; indeed, 
list itself he differentiates such. colour varieties as rubella, 4 
lutea, lilacina, etc., and many interesting problems in COPEY” 
with these banded shells still await solution. Little is ie 
degree in which the variations are inherited, the influence of em 
ment upon the colour and banding, and the courses which dete 
the dominance of certain forms in some localities and the P! 
variety in others, but whether science is really served by the 
and cataloguing of minute variations, whether they actually 
] 
tisk 
R 
mollusca can only result in a feeling of disappointme™ 
__ authors fail to state the limitations of the district they 
