Cobb — Nematodes, mostly Australian and Fijian. 5 



only assert that they must impart to the wall of the pharynx an irregular sculpturing, 

 doubtless well adapting it for mastication, for which purpose the exterior of the 

 pharynx seems supplied with more abundant and more powerful muscles than in the 

 other species. Doubtless these differences can be made the basis of a division of the 

 genus into two natural subgenera. In those cases where the dorsal tooth is placed in 

 the neighbourhood of the lips, I have observed that the anterior walls of the pharynx, 

 or the internal surface of the lips, are armed with large somewhat tooth-like almost 

 backward-pointing processes, which I judge from their position (I have never seen 

 them act) to be the antagonistics of the dorsal tooth. The lips and walls of the 

 pharynx are always supplied with numerous and powerful muscles, concerning whosu 

 action Biitschli remarked that the head was often seen to contract longitudinally. 



The oesophagus is very simple, being a tube half to two-thirds as wide as the 

 neck, wider posteriorly than anteriorly, without bulbs of any sort, and separated from 

 the intestine by a distinct but shallow constriction, which is sometimes double owing 

 to the fact that the intestine is joined closely to the cardia for a short distance and 

 then suddenly expands. The intestine is two-thirds to three-fourths as wide as the 

 body and ends in a short and narrow rectum, only about two-thirds as long as the 

 anal body-diameter. The intestine is usually thin-walled and is composed of cells 

 whose granules are arranged so as to give rise to a tessellation, often of such a perfect 

 and beautiful kind as to render these worms a most attractive spectacle. The nerve- 

 ring surrounds the oesophagus squarely near the division between its anterior and 

 middle third ; before and behind the ring the usual ganglion cells occur. All the 

 species are eyeless. The lateral fields are well developed, being one-fifth to one-third 

 as wide as the body. The lateral organs have remained until now undiscovered in 

 all the species ; I find, however, that in longicaudattis they exist opposite the middle 

 of the pharynx in the form of small transverse ellipsoidal openings. The ventral 

 gland, too, has hitherto remained unseen, but in megalaimus and digiturus a pore 

 exists just behind the nerve-ring, and this pore has every appearance of being the 

 outlet of the ventral o^land. 



o 



The tail varies in length from one-fiftieth to one-fifth of the length of the 

 animal ; when short it is conoid, and when long it is conoid in the anterior part and 

 narrow and cylindroid in the remaining part, being always slightly swollen at the 

 terminus, which is rounded and gives exit to the secretions of the caudal glands, 

 probably always three in number. 



In two species {digiturus and gymnolaimus) the female sexual apparatus is single, 

 in all the others as yet made known it is double, the two parts being symmetrically 

 reflexed, in spite of which fact, however, the projecting vulva is usually situated near 

 the beginning of the posterior third of the body, a position in harmony with the 



