1922.] 



H. A. Baylis and R. Daubney : Parasitic Nematodes. 



295 



tit: 



the female. The maximum thickness is 0-5-07 mm. The lateral fields are broad, 

 and of the type characteristic of the genus, consisting of a single row of some 70 

 large, granular cells with clear, rounded nuclei. There are no lateral alae. No cer- 

 vical papillae have been detected, nor do the longitudinal rows of small papillae on 

 the body, which occur in some species, appear to be 

 present in either sex. The cuticular striation is 

 exceedingly fine. The diameter of the head is about 

 0*06 mm. There are three distinct lips, of somewhat 

 elongate shape, each terminating anteriorly in a flat- 

 tened lobe consisting only of cuticle, which, seen 

 in profile (fig. 31), gives the lip the appearance of 

 ending in a kind of curved tooth or spine. Each 

 lip bears a relatively large papilla on the outer 

 surface of its basal portion. The oesophagus, as 

 has been observed in some other members of the 

 genus, is marked off into a narrow anterior portion, 

 or pharynx, the lumen of which describes a peculiar 

 ventral bend posteriorly; and a wide posterior 

 portion, the oesophagus proper, ending posteriorly 

 in a well-developed bulb. The distance from the 

 anterior extremity of the lips to the posterior end of 

 the oesophageal bulb is about i"i mm. in the male, 

 1*45 mm. in the female. Of this the pharynx oc- 

 cupies o*i8-0'22 mm. The bulb is almost spherical, 

 measuring 0*2-0 -25 mm. in both anteroposterior 

 and transverse directions. The nerve-ring is situated 

 at 0-37-0-39 mm., and the excretory pore at 0-6-0-85 mm., from the anterior end. 



The caudal end of the male (figs. 32, 33) is obliquely truncate, terminating in a 

 small, conical spike. Anteriorly to this there are broad alae, forming an almost 

 circular bursa-like expansion. Near the anterior limits of the alae there is a rounded 

 sucker with chitinous ring, measuring 0-09 mm. in outside diameter, and having its 

 aperture somewhat posteriorly directed. There is a little depression in the posterior 

 edge of the chitinous ring, as in Heterakis. This has been described as a papilla in 

 some species. The two equal spicules, which measure i-i mm. in length and 0-0275 

 mm. in maximum thickness, are covered externally with rather coarse granulations, 

 and taper gradually from their bases to slender points. No chitinized accessory piece 

 appears to be present. There are apparently nine pairs of caudal papillae, of which 

 seven project more or less laterally into the alae, while two are situated ventrally 

 behind the cloacal aperture. As only one male was available, and in this specimen 

 the spicules were extruded, it is not certain whether any further ventral papillae may 

 have been hidden from view by them. Of the laterally-placed papillae, two relatively 

 small pairs are close to the tail-spike, the most posterior being directed more ventrally, 

 the second more dorsally. The next two pairs are very close together and rather 



Fig. 31. — Strongyluris chamaeleonis. 

 Anterior end of female ; lateral view. 



d.i., dorsal lip ; 

 ph., pharynx. 



n.r., nerve-ring 



