92 THE NAUTILUS. 
Our large series shows every possible variation in the develop- 
ment of these characters, from young specimens in which no scar or 
tails (for they look very much like squirrel tails) are visible, to old, 
solid shells with a heavy, snowy, swollen callus, and having these 
brown wings very strongly developed. 
The same characters are seen in Patella (Helcioniscus) argentata 
Sowb., better known as P. talcosa Gld. H. clypeater, which Mr. 
Pilsbry places with Nacella, on account of slight differences in 
anatomical characters, but which, conchologically, seems closely 
allied to P. argentata, and in other species. 
In short, there can be no doubt that this scar and the curious 
radiating brown lines are merely adult characters which are de- 
veloped in quite a number of species. I quite agree with Mr. Geo. 
W. Taylor in believing that this species does not come from the west 
coast of South America, but is probably confined to the north-west- 
ern part of the Indo-Pacific region. 
THE VIRGINIA COLONY OF HELIX NEMORALIS. 
BY T. D. A. COCKERELL, N. M. AGR. EXP. STA. 
There appeared in the Nauri.us, of Nov., 1889, a paper under 
the above title, setting forth some very interesting facts regarding 
the variations exhibited by a colony of H. nemoralis at Lexington, 
Va. Prof. J. H. Morrison, who collected the shells studied, took 
considerable interest in the matter at that time, and had gathered 
together a good deal of information additional to that given in the 
above-cited paper. I have, therefore, been quite disappointed not 
to see any publication by him on this subject, or any evidence that 
the colony has received further attention. 
It is scarcely necessary to dwell on the extreme interest attaching 
to the history of this colony. Here we have a variable species in- 
troduced into a new country, and varying in a most extraordinary 
manner under the influence of the new environment. The peculiar 
variations are very numerous, though, in the main, tending entirely 
in one direction—to the splitting of the normal bands. Although 
the number of individuals thus varying is considerable, very few of 
such have exactly the same formula, whereas, several of the old 
European variations occur in numerous specimens. 
It appears, in the highest degree, probable that these peculiar 
variations are congenital and not acquired during the lifetime of 
