CONTAGIOUS DISEASES OF DOMESTICATED ANIMALS. Ill 



pass to the mouth parts, the latter to the digestive and reproductive 

 organs. 



Secretory apparatus. — The most eminent helminthologists, among them 

 Bastiau, Schneider, and E. Perrier, have seen in certain nematodes 

 secretory structures composed of utricles sometimes double, provided 

 with a canal which opens on the skin in the middle of a i)apilla. These 

 structures have been observed near the posterior extremity of the body 

 in the male, and in the region of the neck in both sexes. We have 

 sought them without success in the Syngamus of the pheasants. Once, 

 however, we saw, quite distinctly, an oblique canal opening on the skin 

 a little below the oesophageal nervous ring and arising from a glandular 

 mass situated in the region, where, in Plate I, Fig. 5, we have shown 

 the i)osition of the longitudinal fusiform muscular fibers. Along the 

 cesoi)hagus and under the same muscular layers there is situated an 

 elongated club-shaped gland, which opens at the base of the pharyngeal 

 capsule (Plate I, Fig. 5, d). This is a true salivary gland ; its walls are 

 lined with ovoid, doubly-nucleated cells. 



Eeproductive apparatus : Genital organs of the male. (Plate II, Fig. 

 7.) — In the nematodes generally the testes consist of a long tube uni- 

 forndy cylindrical in its whole extent from .1 to .2™"" (.004 — .008 inch) 

 in diameter. In the male Syngamus of the jiheasants it presented 

 quite characteristic diflereuces from the known type. It is i)ossib]e to 

 see, through the translucent tissues of the body, and still better when 

 the testicle has been forced out of the body of the worm, a large, abrupt 

 expansion of the tube 1™"" (.04 inch) from its inferior termination. 

 This bag-pipe-like enlargement gradually contracts anteriorly and con- 

 tinues as a cylindrical tube slightly narrower than at its commencement. 

 At the middle of the worm's body it twines about the intestine, then re- 

 descends and terminates in a cul-de-sac near the posterior extremity. 

 The disposition of this seminiferous tube may be better seen when, b}' 

 a fortunate compression,, or a patient dissection, it has been forced out 

 of the body. The three portions of which it is composed may then be 

 readily distinguished : the first as a vas deferens, the secoiul as a vesi- 

 cula seminalis, and the third (which coils about the intestine) as the tes- 

 ticle proper. The latter is filled with an opaque, amorphous substance, 

 thecontents of the vesicula seminalis and the vas deferens being likewise 

 opaque but segmented into granular corpuscles of very varying forms, 

 having each a nucleus of .01 to .03'"™ (.0004 — .0012 inch) in diame- 

 ter. These are the spermatozoids. The vas deferens, about .075""" 

 (.003 inch) in diameter, opens at the posterior extremity of the body 

 in the center of the caudal bursa, between two very small, short, and 

 nearly straight spicules, the extremities of whicli rest immovably in the 

 vagina of the female. Tlie vesicula seminalis, enlarged in tlie lorm of 

 a i)ear, has its walls made uj) of muscular fibers which are all obliquely 

 placed and inserted into a longitudinal raph6 like the barbs of a feather 

 into the shaft. The object of this arrangement undoubtedly is to cause 



