350 



ANATOMY OF THE MALE HOWARDULA 



spherical nuclei two-thirds as wide as the cells themselves; and these nuclei 

 carry spherical nucleoli half as wide as the nuclei themselves. The inter- 

 spaces in the chord are nearly filled by granules of variable size, the largest one- 

 sixth as wide as the nema. The chords narrow in the tail to near the terminus. 

 Possibly there are faint refractive elements in the inconspicuous lining of the 

 oesophagus indicating the presence of a vestigial bulbous body. In the specimen 

 under examination the cells near the blind end of the gonad have considerable size, 

 being about one-fourth as wide as the body. 



Male: *J ^ -Z- *J ^ ?J O .G1 Striae, 1.2 mi- 



crons apart, rather readily resolvable with high powers. As in the female, there is 



no perceptible framework to the lip re- 

 v gion, but six very flat lips can be faintly 

 M seen. No papillae have been distin- 

 guished on the lips. The tail presents a 

 terminal dimple. There is very little 

 vestige of a spear in the pharynx (Fig. 

 4) but the limits of the pharynx usually 

 can be made out, its length being a 

 little greater than the width of the base 

 of the head. Behind the pharynx, the 

 OfT oesophagus can be seen to be about one- 

 third as wide as the base of the head, 

 and it continues at first more or less nor- 

 mal, but becomes indefinite. There is 

 no distinct O3sophageal swelling, nor has 

 any vestige of such been seen. At the 

 nerve-ring, the oesophagus is probably 

 'IKflKI less than one-third as wide as the corre- 

 sponding portion of the neck. The 

 cesophagus is indefinite behind, but 

 spherical granules, such as are charac- 

 teristic of the intestinal cells, occur 

 about one body width behind the nerve- 

 ring. However, it seems likely that, as 

 in the female, the first appearance of 

 birefringents probably indicates the be- 

 ginning of the vestigial intestine. The 

 blind end of the testis, about one-third 

 as wide as the body, is indistinct, and a 

 little more than twice as far from the 

 ' anterior extremity as the nerve-ring. 

 For about two to three body widths the 



X18 



Fig. 6. Gonads of the female cucumber beetle, 

 Diabrotica tittata, previous to egg-laying, when the 

 nemic larvae swarm into the ovaries. 



testis increases in diameter, becoming 

 half as wide as the body, this portion 

 being rather coarsely and irregularly 

 granular. The anal region is very slightly raised. There are two, nearly straight, 

 tapering, blunt spicula, nearly as long as the anal body diameter. These are 



