GUPPY ON HELICINA 
73 
and well defined group without near allies. Among land 
shells its nearest relations would be among the Cyclostomidce. 
Among marine molluska affinities are indicated both as to shell 
characters and dentition with Neritina and through that genus 
probably with Trochus , Ilciliotis and Fissurella. 
It would, I think, be a great convenience for zoological study 
and classification if every family or genus or other group of ani- 
mals were treated somewhat in the way that the family Helicidre 
is dealt with in the second edition of Albers’ work “ Die Heliceen.” 
Unfortunately some writers or naturalists seem determined to 
spoil every attempt to deal philosophically with classification and 
nomenclature. Albers’ work is doubtless full of errors and will 
bear much amendment. But the principle on which it is based, 
that of giving as wide an extension as nature may admit to 
generic names and dividing each genus into sections, is a most 
useful one. The names given to these sections are not intended 
to be generic names nor ought they to come strictly under the 
laws applicable to generic names. But some authors have un- 
fortunately quite misunderstood this point and have adopted 
Albers’ names as names of genera, whereon an immense amount of 
ink and labor has been wasted in applying to such names the 
rules of priority, &c. 
I exhibit to you a small but valuable collection of Heli- 
cinidrn which I have attempted to arrange in the manner indicated 
and I append a list of the species, showing the proposed genera, 
subgenera and sections into which the species may be grouped. 
Trinidad possesses four species of the genus Helicina all very 
distinct from one another and belonging each to a different 
section of the genus. 
Genus HELICTNA Lamarck 
Subgenus Lucid ella Gray 
Helicina aureola Fer. Jamaica 
Subgenus Stoastoma Adams 
Helicina yisurn Adams J amaica 
