NO. 9 cuckler: nematode parasites 145 



There is a single spicule (fig. 12). The length varies from 1.36 to 

 1.58 (average 1.47) mm., about two fifths of the body length. The 

 proximal end of the spicule is dilated to form a head where the muscles 

 are attached. The distal end of the spicule is sharply pointed. A short 

 distance from the distal end the spicule is enlarged laterally and at this 

 point possesses a curve which is ventrally directed. 



There is a well-developed, V-shaped accessory piece (fig. 14), which 

 measures 0.084 mm. in width by 0.080 mm. in length. The distal point 

 of the accessoiy piece is directed ventrally, forming a conspicuous hooked 

 tip. At the base of the accessoiy piece on each side there is a tubular 

 cavity which seems to open to the outside at the base of the tail. The 

 significance of this structure was not determined. 



Female: The vulva is situated on the ventral surface 0.35 mm. 

 posterior to the middle of the body. It varies from 2.83 to 3.96 (aver- 

 age 3.40) mm. from the anterior end. In the fully mature specimens 

 there is a cuticular flap around the anterior margin of the vulva. Sur- 

 rounding the distal end of the vagina and near the body wall, large 

 gland cells can be distinguished in the immature specimens, but they are 

 not apparent in the fully mature individuals. It seems probable that 

 these gland cells are concerned with the development of the flap around 

 the vulva. The vulva communicates with the muscular vagina which 

 is directed anteriorly and then curves posteriorly where it is continued 

 as a less muscular region, the ovejector. Following this region is the 

 egg reservoir or common uterine stem. In the mature specimens the 

 lengths of the parts of the genitalia average as follows: the vagina 0.90 

 mm., the ovejector 0.90 mm., and the common uterine stem 0.96 mm. 

 The uteri are divergent, thin-walled tubes continuous with the ovaries. 

 The ovaries are about 0.08 mm. in diameter near their mid-regions. The 

 number of eggs in the uteri is variable ; some specimens have nearly the 

 whole body filled with them, while others have very few eggs. The eggs 

 (fig. 9) are large and possess a relatively thin shell. The eggs vary from 

 0.077 to 0.098 mm. in width by 0.175 to 0.196 mm. in length, with an 

 average size of 0.086 by 0.185 mm. The eggs are segmented in utero. 



SPECIFIC DIAGNOSIS OF ALAEURIS LONGISPICULA 



Principal characters of genus. Mature females 5.28 to 7.77 mm. by 

 0.47 mm.; males 3.01 to 4.27 mm. by 0.28 mm. Cephalic region dis- 

 tinct; three conspicuous lips; lateroventral lips each with four papillae 

 and an amphid ; dorsal lip with two papillae. Lateral cuticular alae ab- 



