304 Macreay Memoriat Vouume. 
EXPLANATION OF PLATES. 
PLATE XXXVI. 
MoNONCHUS DIGITURUS. 
Fig. 1. Female worm. Fig. 2. Terminus of the tail. Fig. 3, Neck and head. Fig. 4. Tail. 
a, spinneret ; b, mouth-opening ; c, papille; d, pharynx; e, two submedian teeth ; f, single dorsal 
tooth ; g, nerve-ring ; h, cesophagus ; 7, vulva ; Jj, anus ; k, intestine ; 7, cardiac constriction. 
MononcHvus GYMNOLAIMUS. 
Fig. 1. Female worm. Fig. 2. Head of the same worm more highly magnified. Fig. 3. Anal region. 
a, papille round the mouth ; 6, papille on the margin of the head; ¢, rectum ; d, lateral organ ; ¢, 
striz on wall of the pharynx; /, muscles of the pharynx; g, esophagus ; h, caudal glands; 4, 
dorsal tooth ; 7, esophagus; &, intestine ; J, vulva and vagina ; m, ovum, flexure in ovary; 7, 
anus ; 0, excretory pore (?) ; p, cardiac collum ; g, cesophagus. 
MOoNONCHUS MINOR. 
Fig. 1. Female worm. Fig. 2. Head of the same worm more highly magnified. Fig, 3. Neck and head. 
Fig. 4. Tail. Fig. 5. Portion of body. 
a, papille on the margin of the head ; 0, papillz round the mouth; ¢, dorsal tooth ; d, rasp-like teeth 
on wall of the pharynx ; e, beginning of the esophagus; f, nerve-ring; g, anus; 4, lateral 
field ; ¢, vulva ; j, egg ; k, esophagus. 
RHABDITIS FILIFORMIS (2), 
Fig. 1. Female worm. Fig. 2. Head. Fig. 3. Head. Fig. 4. Portion of the body. 
a, pharynx ; b, beginning of the esophagus; c, esophagus; d, cardiac bulb ; ¢, flexure in ovary; /, 
blind end of ovary; g, vulva; h, blind end of ovary; %, posterior end of pharynx ; j, anus; 
k, flexure in intestine ; 1, egg. 
PLATE XXXVII. 
AULOLAIMUS EXILIS. 
Fig. 1. A female worm. Fig. 2, Head of the same worm. Fig. 3. Neck. Fig. 4. Cardiac region. 
a, lips; 6, pharynx ; ¢, nerve-ring ; d, base of pharynx; e, vulva; f, anus; g, esophagus; h, cardiac 
bulb ; ¢, cardiac bulb ; j, beginning of the intestine. 
