LITTORINID. 335 
I have been wishing for an apt opportunity to issue my paper, 
which only occurred in the April Number of the ‘ British 
Mollusca,’ wherein malacologists will observe that Professor 
Forbes, with singular coincidence, by his views, corroborates 
mine, written many months ago, from actual examination of 
the animals. Though the learned Professor has admitted into 
his work varieties that have not the slightest pretensions to be 
styled species, for the sake of exciting further investigation of 
them, yet in page 52 of his summary of the Littorine, he 
boldly and emphatically repudiates all paternity with the 
pseudo-species. He says— 
“In the preceding account of the Littorine several are 
described as species which many of our ablest naturalists 
regard as varieties, whilst others are considered as varieties 
which some hold to be worthy of specific rank ; our conviction 
is, that the result of a completed knowledge of this genus 
would be a reduction in the number of true British species. 
Taking the most permanent features of the animal and its 
shell as our guide, we are inclined to reduce the true spe- 
cific types to L. neritoides, L. littorea, L. littoralis and 
L. rudis.” 
My views being thus supported, I send forth without hesita- 
tion these observations made long ago, and I feel gratified 
that my investigations of this tribe have received the corrobo- 
ration enunciated by that eminent Professor. 
Before I give the descriptions of the types of the genera of 
the Littorinide, I will make some remarks on the prevalent 
practice of naturalists to create species from mere varieties : 
this anxiety can only be attributed to their wish to extend 
our knowledge of new and interesting objects. That these 
views are desirable and laudable cannot be questioned, but it 
is to be feared that the zeal of these gentlemen, combined 
with the ardour of rivalry in the race with their brethren in 
the same pursuits, have been the cause of a departure from 
those principles and laws which are considered indispensable 
to arrive at just conclusions in the establishment of genera 
and species ; or in other words, in laying down the true bases 
of the differential features of the families, genera and species 
