856 Mr. W. Clark on the Littorinide. 
great impulse from that valuable work, ‘The British Mollusca,’ 
wherein the learned Professor and his coadjutor have boldly 
broken through the trammels of the old system, and as far as 
possible, founded the classification on natural organization, and 
at a great expense of arduous research, though still from neces- 
sity retaining hundreds of unmeaning and worthless synonyms, 
expunged and weeded out a multitude of exotic species which 
disfigured and almost choked up our indigena ; these are great 
services, and every naturalist in this line will feel a lively satis- 
faction, that by these aids he can now pursue a delightful study 
agreeably to the order of nature. A new era has commenced in 
British malacology ; it stands disenthralled from arbitrary and 
defective dispositions, and in future will march hand in hand 
with its elder sister, conchology. And lastly, that I may not be 
misunderstood on the subject of the varieties, I beg to state, that 
I consider the mention of all, very desirable and of great import- 
ance as varieties, but not as species, and on this point I give an 
extract from a deservedly high authority. M. Philippi says, 
“Semper varietates sedulo notavi, hoc etiam valde necessarrum 
duxi, cum auctores qui in muszeis modo conchylia describunt, 1d 
minus apte facere possint, quam ille qui centena specimina in 
maris littore ipse colligit et observat ; sed nimium plerumque 
colori, aliisque notis variabilibus, dignitatem tribuant, aut etates 
diversas pro speciebus diversis sumant, sicut ex. gr. multoties 
clarissimus Risso fecit.” This opmion is expressly given sub 
modo, that especial care is to be taken that varieties are not in- 
serted as species. 
It now remains by examples to illustrate and impress on the 
minds of young naturalists the value and pressure of the prece- 
ding observations. Perhaps a stronger case of the improper mul- 
tiplication of species on frivolous grounds cannot be brought for- 
ward than that of the genus Anomia, which, as I believe, only 
contains a single British species, the Anomia ephippium, the mere 
varieties of which have constituted the sixteen or seventeen spe- 
cies that are consigned to our conchological annals, and are based 
on the arbitrary and artificial distinctions of colour, the various 
adscititious markings, and forms resuiting from the substances 
on which they are fixed, combined with the influencing effects of 
habitat, food, and depth of water. 
I have the last summer examined and dissected 500 Anomie 
of all forms, sizes and colours from different habitats, and in the 
endless variety of colour and markings of this proteiform genus 
I have not discovered a single specific character, either as regards 
the anatomy or external organs of this genus, that would justify 
the creation of a single species. I have now done with the Ano- 
miz, as the learned editozs of the ‘ British Mollusca’ have, though 
