128 H. CHARLTON BASTIAN ON THE STRUCTURE AND 
The obscurity of this process and our inability to explain its nature should of course 
be no barrier to our acceptance of it as a fact, if this be in accordance with all the 
evidence that can be brought to bear upon the subject. And, in reality, what clearer - 
insight do we gain into the essential nature of the process by which new organic beings 
are generated, by supposing the germ-cells of the female to be subjected to the influence 
of certain cell-products of the male? By long habit and association, indeed, we are apt to 
think, when this occurs, we have all that is necessary for the explanation of the process, 
whereas in truth it is but the throwing in of another unknown term into the problem— 
an attempt to resolve “ignotum per ignotius.” Nor can we expect to be able to 
solve all the difficult phenomena of reproduction, when other common organic processes 
of growth, development, and secretion are in themselves so obscure. Professor Huxley 
aptly remarks on this subject, * When we know why, in a mass of tissue of identical 
structure throughout, one part becomes a brain, another a heart, and a third a liver— 
when we can answer these every-day questions of the Sphinx, we may attempt her more 
difficult riddles without running too great a risk of being devoured." 
Should future investigation confirm the opinion that the Guineaworm enters its host 
at a very early stage of its existence, and before the development of its sexual organs, its 
remaining in this situation till young are produced and ready to be brought forth, is a 
phenomenon different from what usually oecurs, and also from what is met with in the 
nearly allied Gordius and Mermis, with reference to which Von Siebold has established 
that the immature worms penetrate the bodies of insect larvee, and after remaining there 
some time, emerge from the bodies of their hosts, and then only, in the free stage of their 
existence, develope organs of reproduction, ova, and young. Siebold says*, “ Ainsi à 
raison des faits que je viens d'exposer, on ne rencontre jamais certaines Helminthes hors 
du corps de leurs hótes naturels à moins que leur croissance ne soit achevée; et certaines 
espéces aussi ne se voient dans l'intérieur du corps des animaux dont elles doivent étre 
les parasites que lorsqu'elles sont déjà parvenues à une taille déterminée." This dif- 
ference in the two groups of Entozoa mentioned depends upon the necessity of the 
conjunction of the two sexes for the fertilization of ova; but there is a third class, com- 
prehending the Tenie and other hermaphrodite worms, which, from the absence of such 
a necessity, are enabled to pass through the whole cycle of their development in one or 
more different animals; and in a subdivision of this class we must assign a place for the 
Guineaworm, since, having a power of producing young by an agamic process, it remains 
in the condition of a parasite through nearly the whole period of its existence. 
As before stated, all the specimens of Guineaworm hitherto carefully examined have been 
found to be female and viviparous; and the only writers who mention male worms (so far 
as I have been able to discover) are Professor Owen, M. Leblond, and Dr. M‘Clelland; 
but in each case the observations are, as will be seen, incomplete, and scarcely definite 
enough to turn the overwhelming balance of evidence on the other side. 
: Professor Owent gives a figure of what he considered a male Guineaworm, and says, 
‘The caudal extremity of the male is obtuse, and emits a single spiculum ; in the female 
* “Sur la Production des Helminthes," Ann. des Sciences Nat. tom. v., 1855. 
T Art. Entozoa, Cycloped. of Anat. & Physiol. part x. (1837) p. 122. 
