LEPTONCHUS, AXONCHIUM 



305 



that its cross-section presents but two of them. These cells are packed with 

 granules of variable size, the largest having a diameter one-eighth as great as 

 that of the body, while the smallest are very minute. The tail begins to taper 

 from some distance in front of the anus. There are a few inconspicuous papillae 

 near the posterior extremity of the tail of the female. The pre-rectum is of 

 most unusual length, extending to a little beyond the flexure of the anterior 

 ovary, and hence occupying about half the length of the body. It is set off from 

 the front portion of the intestinal tube by a distinct constriction, and differs also 

 in structure. The lateral fields are about one-third as wide as the body. The 

 ventral fields appear to be wider than the lateral, nearly half as wide as the body, 

 at least appearances half way between the vulva and the anus give rise to this 

 measurement. The traces of the excretory pore are difficult to observe, but they 

 are uniform in the different specimens, and as no other similar "break" in the 

 cuticle is to be deciphered it seems impossible that the single "break" opposite 

 the nerve-ring can be anything but an excretory pore. No indications are seen 

 of the existence of an internal structure connecting with this 

 pore, but the neck, especially the posterior portion of it in front 

 of the cardiac swelling, is occupied by elongated structures, 

 which may be of a glandular nature and connected with the 

 aforesaid "pore." The slightly elevated vulva is a trans- 

 verse slit about one-fourth as long as the body is wide. Radi- 

 ating from its ends are four muscles passing to the submedian 

 fields. The vagina leads about halfway across the body. The 

 reflexed ovaries reach about three-fourths the distance back to 

 the vulva, and contain a dozen or more developing ova, 

 arranged somewhat irregularly. The elongated eggs are three 

 to four times as long as the body is wide, and about one-fourth 

 to one-fifth as wide as long. 



Habitat: Soil about willow trees, Arlington Farm, Va., oppo- 

 site the city of Washington, D. C., U. S. A. Fig. 85, p. 304. 



.2 6.7 34. 55'" 98.8 9 9 



86. Axonchium amplicollen. sp. ' 6 (7) / 1 ' 9 2 ' 8 

 Cuticle naked. The two portions of the ]b(6) 

 oesophagus are separated by a constriction, 

 as shown in the figure; both parts cylindri- 

 cal. Lining of the oesophagus well-devel- aai P" 

 oped, but more or less obscured by the 

 well marked, rather coarse, colorless muscu- 

 lature in the posterior part. Salivary glands 

 in the posterior part of the oesophagus as in 

 Dorylaimus, one gland emptying into the 

 lumen near the anterior portion of the 

 larger cylindroid half of the oesophagus, 

 the others farther back. Anus subcon- 

 tinuous; the rectum prominent and cutin- 

 ized, and one and one-third times as long 

 as the anal body-diameter. The anal mus- x750 

 cles are clearly disclosed. The pre-rectum is five times as long as the anal body- 

 diameter, and set off by a definite but faint constriction. The cells of the intes- 

 tine contain numerous, colorless granules of variable size, the largest of which 

 are one-twenty-fifth as wide as the body. Tail of the adult female as shown in 

 the illustration. In the youngest larvae, however, the tail is cylindroid in the 



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