94 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 2 



GENERIC DIAGNOSIS OF IGUANACOLA 



Medium sized Pronocephalids, body smooth and elongate in 

 extended forms, bearing a low muscular collar complete dorsally, 

 interrupted ventrally by oval depression. Oral sucker subterminal; 

 esophagus simple; intestinal ceca narrow, irregular, but without dis- 

 tinct side branches. Genital pores separate, close together near inner 

 edge of left cecum. Testes symmetrical, lobed, near posterior end 

 of body; seminal vesicle long and coiled; cirrus small, conical, and 

 muscular, in a terminal chamber. Ovary pretesticular, in median 

 line; shell gland just posterior to ovary. Uterine coils overlap ceca. 

 Vitellaria extracecal from anterior level of testes to posterior level 

 of cirrus. Eggs with a long filament at each pole. Excretory vesicle 

 Y-shaped with anastomosing branches. Parasitic in intestine of 

 marine iguana, Amblyrhynchus cristatus. Type species: Iguanacola 

 navicularius. 



SPECIFIC DIAGNOSIS OF IGUANACOLA NAVICULARIUS 



(Measurements in mm.) 



Body smooth, elongate, four and one-half times longer than wide, 

 highly muscular, cup-shaped when contracted. Length 6.63 to 8.80, 

 width 1.30 to 2. Oral sucker on ventral surface at anterior end, 

 slightly wider than long, 0.6 wide, 0.57 long. Esophagus short with 

 enlargement at anterior end. Ceca narrow, reaching nearly to pos- 

 terior end of body, ventral to inner edges of testes, with short irregu- 

 lar outpocketings on outer margins. Genital pores separate but close 

 together, slightly to left of and anterior to mid-body. Testes with 

 distinct lobes, symmetrical, near posterior end of body. Seminal 

 vesicle coiled, free in parenchyma, extending from just anterior to 

 testes to posterior end of cirrus sac. Cirrus sac large, about five times 

 as long as wide, extending from seminal vesicle diagonally to margin 

 of right cecum, and continuing diagonally in opposite direction to 

 mid-line and genital pore; prostatic region large, occupying greater 

 portion (about nine tenths) of cirrus sac, with strong constriction 

 present in middle portion. Cirrus small, muscular, projecting nipple- 

 like into terminal chamber which surrounds it except at basal portion. 

 Ejaculatory duct communicates with anterior terminal chamber of 

 cirrus, and posteriorly with flattened sinus at base of cirrus. Ovary 



