VOL. III., NO. XXII.—JULY, 1838. 
SOME REMARKS ON SPECIFIC DISTINCTIONS. 
By Peter Rylands, Esq. 
At p. 20 of the second volume of The Naturalist , noticing the difficulty of 
testing the validity of certain presumed species of insects, I remarked that 44 should 
there be found specimens which vary in such a manner as to form a connecting 
link between the supposed species and the established one, the true value of the 
former is at once understood”-—believing that, in such a case, it ought to be 
considered a mere variety. Mr. Blyth, doubting the correctness of this opinion, 
favoured the readers of The Naturalist (Vol. II., pp. 288, &c.) with some obser¬ 
vations on the subject, the general tenor of which was sufficiently gratifying to 
me to induce a feeling of indifference to, if not forgetfulness of, the cause which 
led to their publication. After this long interval the subject would not have 
been recurred to on my part, did I not believe that good must result from a 
calm and candid discussion of the question at issue, and that it well merits further 
consideration. 
Cuvier defined a species to be 44 the assemblage of individuals, descended one 
from the other, or from common parents, or from such as resemble them as 
strongly as they resemble each otherand varieties, 44 the accidental sub¬ 
division of species.” 
Kirby and Spence remark that 44 a species is a natural object whose differences 
from those most nearly related to it had their origin when it came from the hands 
of its Creator; while those that characterize a variety have been produced since 
that event.” 
Notwithstanding these strict definitions, naturalists have long been puzzled to 
discover some certain diagnostic whereby a variety may be distinguished from a 
species. 1 The authors last quoted ( Introduction to Entomology , Vol. IV., p. 397) 
state that, 44 in general, where there is no difference in form$ appendages , and 
.organs, proportions, scidpture, and larvae;—colour alone, especially in insects 
inhabiting the same district, only indicates a casual variety.” Dr. BurmeIster re¬ 
marks ( Handhach der Ent., p. 588) that 44 one important character whidti especially 
identifies the sub-species [or variety] with the species is, that they are fertile 
2 z 
VOL, III.—NO. XXII, 
