570 



APPENDIX 



¥■ 



ventricle, ileum, colon, rectum ; salivary glands and 

 receptacles ; pyloric caeca ; Malpighian tubes ; cerebral 

 ganglion (Fig. 183). 

 Remove, stain, and mount in balsam a salivary gland and 

 receptacle, and also remove and mount a portion of fat body 

 with tracheae. 

 Remove the alimentary canal. Note : cerebral, subcesopha- 

 geal, thoracic, and abdominal ganglia ; and the commissures 

 connecting them ; in female, 

 colleterial glands, oviduct, 

 spermatheca, ovarian tubes (Fig. 

 183); in immature male, testis, 

 vas deferens, mushroom-shaped 

 gland ; in mature male, mush- 

 room gland, its duct, accessory 

 gland. 

 10. Examine under a microscope 

 the stained salivary gland ; the 

 fatty tissue with tracheae (Fig. 

 185); an ovarian tube (low 

 power) ; contents of mushroom 

 gland ; muscular fibre (striped). 

 The most convenient source from 

 which to obtain speci- 

 Ascarls. mens of Ascaris is the 



pig, which is infested by 

 a species closely similar to, if not 

 identical with, A. lumbricoides. The 

 related but larger A. megalocephala 

 from the horse is also often available. 

 The worms should be preserved in 

 formalin. 



2. Note, in specimens of the two 

 sexes : smooth cuticle, anterior 

 and hinder ends, excretory pore, 

 genital pore (Fig. 203). 



3. Examine under a lens the ends 

 of the body. Note : lips, pa- 

 pillae ; curved tail of male, with 



penial seta; ; tail of female 

 merely convex, without setae (Fig. 204). 

 4. Cut open the worms a little to one side of the middle line, and 

 pin out the body-wall. Unravel the genital organs. Note : 

 pharynx, intestine, rectum ; lateral lines ; dorsal and ventral 

 lines ; in male, testis, vas deferens, penial setae in sheaths ; 

 in female, ovaries, oviducts, uteri, vagina (Figs. 208, 209). 

 10. In a transverse section of the intestinal region, note : cuticle, 

 epidermis, muscle layer ; lateral lines ; dorsal and ventral 

 lines ; intestine ; ovary or testis ; uterus or vas deferens 

 (Fig. 205). 

 Observe a muscle fibre under high power (Fig. 206). 



Fig. 407. — The heart and 

 neighbouring structures of 

 a cockroach : somewhat 

 diagrammatic. 



a.m.. Areas marked by_ dotted lines 

 to show the position of alary 

 muscles below the fatty body ; 

 f,b. y fatty body ; ht., heart ; 

 tr.. trachea?. 



