80 MR. H. CHARLTON BASTIAN’S MONOGRAPH 
* Systema,’ under Ehrenberg's genus Anguillula (which is characterized in such genen] | 
terms as to be perfectly capable of including the most diverse types) he places ser ki 
species of minute Nematodes found in the intestines of insects, myriapods, and other 
animals, which were, for the most part, named by their original discoverers either Asem. 
rides or Oxyurides. An examination of the extremely imperfect descriptions given by 
him, as well as of the figures by their original discoverers ', seem rather to confirm the 
former position assigned to them ; and from a consideration of the facts before mentioned, 
I certainly should not be disposed to place in the same genus parasitic and non-parasitie 
forms without more distinct evidence of their identity in anatomical details than weg 
present possess’, 
Since the classification of the Nematoids generally is in such a confessedly unsatis. 
factory condition, it is quite impossible to indicate the precise position or affinities of 
these non-parasitic forms. It seems, however, most desirable to retain for this group 
the family name of AnGUILLULIDE, proposed by Gervais and Van Beneden °, which i 
not only generally suitable, but is also recommended by the fact of the most familiar 
and first-discovered species having still retained for them the generic name of 4j. 
guillula. 
In the description of species and genera, and the arrangement of the former into the | 
latter groups, an extreme amount of confusion prevails concerning almost all the form | 
hitherto discovered. This seems to have arisen partly from the meagre descriptions ani 
indefinite figures given, and partly, with more accurate and precise observers suchas | 
Eberth, from their not having definitely settled what should be looked upon as points! | 
generic importance. Some of this confusion I hope to be able to clear up in the more 
special portion of this memoir, and also to indicate, as far as my observation has ex 
tended, the value of different anatomical peculiarities as guides to classification. 
Having thus sketched the history of our knowledge concerning this group of animal, | 
I will now add a few details regarding their structure, habits, and mode of life. I shal | 
merely give a brief outline, however, of their anatomy, as I intend to make this the sub + 
Ject of another communication. 
er " leg ment is mostly very transparent and hyaline in appearance, of a chitinow 
composition, and presenting sometimes transverse lines or dots, at others longitudinal 
markings‘, either alone or with transverse also; whilst in the remainder the infeg | 
o bom perfectly plain, with no striæ of any kind. I have discovered numerous 
us Wee oe the integument, establishing a communication, apparently, | 
BELL... CHE € and the poches lateral and median lines of ied 
vendi kad UEM vary much in their number and arrangement n 
, promise to throw considerable licht upon the nature of the curious lateri 
: i Enc = M ateti; and it seems best to 
ithson, Cont. 1 ; 
P ois 893, v. p. 46, tab. 7. f. 6, 7). + Zoologie Médicale. 
confounded with the longitudinal museular bundles seen through an unstriated inte 
