104 11. CHARLTON BASTIAN ON THE STRUCTURE AND 
integument, but, after careful examination of three specimens, was quite unable to dis- 
cover any írace of either generative or digestive organs. After briefly describing the 
external characters of the minute contained worms, he adds, ** What is most remarkable 
is, that these embryos are not, as in Strongylus and the Nematoid genera above men- 
tioned, enveloped in an egg-covering, nor are they included in a special generative tube, 
but float freely along with a granular substance in the common muscular envelope of the 
cavity of the body,"—an observation already made, as above cited, by Rudolphi. 
In his more recent work*, Professor Owen is altogether silent as to the existence or 
non-existence of either generative or alimentary organs; but, speaking of the integument 
of the Nematoid worms, he says, * In the Nematoid parasites of the human subject and’ 
in almost all the order, it is more or less smooth: it consists of a thin, compact epidermis, 
and of a fibrous corium firmly attached to the outer transverse muscular fibres. ‘The 
corium consists of decussating fibres." It will be seen hereafter that nearly all these 
statements are at variance with subsequent observations, and that Leblond's description 
was probably perfectly correct, though Professor Owen doubts its accuracy. 
Rudolph Wagner partially examined two specimens of the Guineaworm, and has 
given a description of them with figures}, as an introduction to a commentary by Birk- 
meyer}. He describes the head, with its four papillæ, and the hooked tail, but does not 
mention any difference in the size of the separate papillee. He speaks also of an anal aper- 
ture at the inner curvature of the tail, serving at the same time as an outlet for the genital 
organs, and marks its situation in a figure. Seeing a white tube running through the 
whole extent of the body, he says, “Hoc intestinum pro ovario habui; nam ex inci- 
sionibus quas in variis corporis locis institui, fila tenuissima (fig. 5 ره‎ b, c) extrahere 
potui, que quominus pro prole habeamus, nihil obstare videtur." The specimens were 
not further dissected, as they were destined for the Zoological Museum of Erlangen. 
Dujardin$ gives no particulars concerning the anatomy of the Guineaworm, save that 
the mouth is simple and round, the tail a little acute and recurved, and that all specimens 
hitherto found have been female and viviparous. 
Mr. Busk| gives a much fuller and more accurate account of the anatomy of the 
Guineaworm than any we have yet met with, and is indeed the first writer who has 
furnished us with anything like a detailed description of this interesting Entozoon. 
Owing to the great rarity of meeting, in this country, with a worm having its anterior 
extremity uninjured, he is not very certain about the anatomy of the head, but agrees 
with other observers as to the acutely inflected tail, and gives figures of different varieties. 
He considers the integuments to be composed of two tubes, between which are con- 
tained the two longitudinal muscles. The external tube is a transparent, striated, elastic 
structure, whilst the internal is composed of a soft pulpy substance covered with a deli- 
* Lect. on Comp. Anat. and Phys. of Invert., London, 1855. 
` T Wagner's is the only correct figure of the whole Guineaworm I have met with; but the anterior extremity is more 
blunt and abrupt, and the lateral papillae larger, than in the specimens I have examined. 
+ Birkmeyer, De Filar. Medinensi Comment., Onoldi, 1838. 
$ Hist. Naturelle des Helminthes, 1845, p. 44. 
|| Transactions of the Microscopical Society, vol. ii. p. 80, 1846. 
