348 



ANATOMY OF ADULT HOWARDULA 



THE SOIL-INHABITING MALE AND FEMALE HOWARDULA, FIG. 4. 





Female. X 3. : '- "iS " ' '^8 ' ' ' "III - 57 m The colorless 



cuticle is traversed by plain transverse striae, all alike, 1.3 microns apart, some- 

 what difficult of resolution except with the highest powers. Very slightly oblique 

 longitudinal striae, due to the attachment of the musculature, are 

 visible in most regions of the body. Xo series of pores have been 

 seen in the cuticle. The lips are amalgamated; the lip region has 

 no apparent framework. Xo labial papillae have been seen. Be- 

 hind the pharynx the oesophagus is about one-fourth, at the nerve- 

 ring about one-fifth, as wide as the corresponding part of the neck. 

 The beginning of the intestine is somewhat indefinite; but proba- 

 bly is indicated by the anterior limits of the minute, elongate bire- 

 fringents, grn bif, Fig. 4. A dorsal oesophageal gland empties 

 through a duct and ampulla near the base of the spear. Two large 

 coarser glands empty a trifle farther back. These glands, Fig. 4, 



Fig. 4. Profile view of the soil-inhabiting male and 

 female of Howardula benigna. The female has a well 

 developed spear; the male none. The female has three 

 strongly developed cesophageal glands; the male none. 

 As in some mermithids, and in some triplonchs, the 

 oesophageal glands are of two kinds, the dorsal gland 

 differing in structure from the two submedian ones. 

 See gl sal dsl and gl sal subm. This difference in struc- 

 ture suggests a double function. The abbreviations 

 are self explanatory. 

 The different zones 

 in the vas deferens 



tsl mvmm 



generations of sperma- 

 tidia, somewhat 

 as in Spirina. on 

 xst, vestigial onchium 

 of the male. 



J 



X400 



are reminiscent of those in the neck of mermithidae (e.g. Agamermis larvae) and 

 of Tylenchus and Heterodera. The striking difference in the composition of the 



