82 MR. H. CHARLTON BASTIAN’S MONOGRAPH 
genera the uterus and ovaries are formed apon the same type; and in those excep. 
tional cases where the posterior segment remains undeveloped, it may still be seen ina 
rudimentary condition in the genus Tylelenchus (Pl. X. fig. 113), whilst in others little 
or no trace of it can be recognized in the adult animal. The male organs consist usually 
of a long tube proceeding from the junction of two elongated sacs or testicles, which 
occupies the ventral aspect of the body, and terminates at the anal cleft, or, as in Mop 
hystera ambigua and M. disjuneta (Pl. IX. figs. 12, 13), a little anterior to it. In two 
species, M: ambigua and Diplogaster filiformis, I have failed to detect any horny intro. 
mittent spicules, whilst in the remainder I have always found two equal spicules, either 
alone or with one, two, or four accessory pieces. 
The glandular and water-vascular systems are so intimately connected with one 
another, that it seems best to include in the same notice what little I have ascertained 
concerning their relations. "The whole inner surface of the body is lined by a glandular 
substance, more highly developed in some species than in others, similar to what I 
described in the Guineaworm, and to what has been met with in some of the parasitie 
Nematoids by Eberth and other observers. In addition, in several species there am 
one or two pyriform glandular masses connected with the vagina (PL XI. fig. 147; 
PI. XIII. figs. 189, 192), and also others near the anal cleft (Pl. XI. fig. 143; Pl. XIII 
fig. 226), whieh have already been observed by Eberth, and termed by him “ vaginal” 
and “anal glands" respectively. He has also described and figured two or three elon- 
gated saes proceeding from the posterior extremity of the body, and has termed them 
tail-glands (Schwanzdrüsefi) : these I had observed also, but, from the fact: of their being 
most developed in those species in which the caudal sucker is largest, and from their 
not presenting the usual granular appearance of the other unmistakeable glands, I have 
always looked upon them rather as contractile sacs in some way connected with the 
operation of the sucker, and shall speak of them henceforth as sucker-tubes (Pl. XL figs. 
126, 151). In nearly all the marine species, I have recognized a glandular exeretory 
organ, ‘opening by means of a long duct on the abdominal aspect of the cesophageal 
portion of the body (Pl. XT. fig. 151; Pl. XII. fig. 164), but have found no structure 
precisely answering to this in the land and freshwater species, though in four of these 
Sc Tylelenchus, Plectus, Aphelenchus, and Cephalobus—the members of which all 
possess the same remarkable tenacity of life—a modification of the same organ evidently 
exists. In these genera I have failed hitherto to detect the entire structure, and have 
| ed Succeeded in recognizing the curved, more slender, and rigid duct with which it 
| terminates (PI. X. figs. 79, 97, 104, 112). Two lateral cellular canals, essentially similar 
ooo gaa fat-canals or lateral lines of the parasitic Nematoids, are met with, wel 
sies. ad 4 HEAR between Which and the external medium I have — enabled 
Me wg communications by means of a variable number of iit | i 
pc Md of the four land and freshwater genera above mentioned 1 Le 
r eei aug | z i 
Pis, idi keel enin =. to have been recognized by Eberth at the anterior and posterior on E 
considers and = ks o se - Puta totally different interpretation upon the appearances he observed, since be 
| T- s of them as skin-glands (Hautdrüsen), loe, cit, p. 6. 
