326 Dr. L. Orley on Hatr-worms. 
appear to be a preponderance of males. Generally speaking, 
it is impossible to establish a fixed rule in this matter, either 
from the form or size of the body, as in certain species it is 
sometimes the males and at other times the females that attain 
the greater length. As the existing species are not represented 
by very many examples, I have not been able to submit any 
Specimens to anatomical investigation, and have been obliged 
to content myself with a study of their external characters. I 
have, however, subjected the cuticula of each species to micro- 
scopical examination, and grouped them in accordance with 
the structure of this layer; it is, indeed, the one characteristic 
feature which, as the best, and, in fact, only practicable one, 
has been always adopted up to this time. I must remark that 
the cuticula separated from the muscular system has not been 
treated with any reagents, as its structure is best observed 
under water. Indeed it is generally impossible to determine 
species properly without a knowledge of the structure of their 
cuticula; and [ have therefore given the microscopical struc- 
ture of the same both in the case of the new species and of 
Baird’s type specimens *. 
I find it also desirable to add a table for identifying the 
existing species in the collection, and to characterize them 
briefly according to their most striking points. In addition to 
the literature of the subject, I have given an account of the 
localities where the specimens were found. This last presents 
much that is interesting in regard to the geographical distri- 
bution of the Gordiide, as the same species is found in 
different zones. 
The species are generally divided into two groups, accord- 
ing to the structure of the cuticula, viz. to those that are 
smooth and those that are granulated. A closer microscopical 
investigation establishes this, and at the same time enables 
us to form a more exact division. I arrange the Gordide in 
two groups, according as the cuticula consists of only one 
system of lines crossing each ‘other, or, on the other hand, 
these lines are either wanting or along with the papilli- 
form granulation compose the cuticula. ‘The first group is 
divided into those that have cross lines, and those that have, 
together with these, a facetted network (fig. 3). The second 
group contains species in which either the whole cuticula con- 
sists of papilliform granulations (fig. 4), or where they are 
dispersed, and consequently have the appearance of being 
imbedded in an intermediate substance (figs. 5.and 7). 
* «Catalogue of the Species of Entozoa contained in the Collection of 
the British Museum’ (London, 1853) ; and ‘ Proceedings of the Zoological 
Society of London,’ 1858, pp. 20 & 21. 
