414 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 2 



sac, beginning just anterior to ovary, curving around left side of acetabu- 

 lum to genital pore. Near the pore, the vesicle narrows to a fine tube; 

 cirrus and cirrus sac lacking; prostate gland not evident, probably lacking. 



Ovary large, median, multilobed, immediately anterior to level of 

 testes. Seminal receptacle large, dorsal, and slightly anterior to ovary. 

 Laurer's canal present. Uterus extending backward in lateral coils in 

 right half of body to near ends of ceca (about % distance between ovary 

 and posterior end of body), then coiling forward in left half of body 

 to genital pore. Eggs brown, elongated, tapering toward one pole, 20 to 

 25 by 9 to 10 fx. Vitellaria in 2 groups, extending from posterior edge of 

 acetabulum to posterior edges of testes; some follicles extracecal; a few 

 are ventral to ceca and to testes; most are dorsal, extending medianly to 

 or almost to ovary which separates the 2 groups. Excretory vesicle large, 

 much inflated, Y shaped, forking near ovary, with crura reaching to 

 anterior end of body. Excretory^ pore terminal or ventrosubterminal, 

 with conspicuous radial muscle bands. 



Discussion. P. americanus differs in several respects from P. acantho- 

 stomus Yamaguti, 1934, the only other species in the genus. The body is 

 broader in its anterior half, the oral sucker is more posterior in position, 

 the ovary and testes are more anterior, the ceca are farther apart, and 

 the eggs more elongate. There are more oral spines in P. americanus (52 

 to 57 as compared with 49), and the preoral chamber seems to be unique. 

 The acetabulum is relatively larger in P. americanus. 



It is of interest to note that P. acanthostomus is from a related host, 

 Lutianus vitta. 



Yamaguti classified Paracr^'ptogonimus in the Acanthostomidae 

 Poche, 1926, although noting that Fuhrmann considered the related genus 

 Cryptogonimus in the Heteroph^ndae. Yamaguti lists as related genera: 

 Cr\'ptogonimus Osborn, Biovarium Yamaguti, Allacanthochasmus Van 

 Cleave, and Caecincola ^Marshall and Gilbert. Siphoderina ]\Ianter, 1934 

 was named at about the same time that Yamaguti's paper appeared. It is 

 a closely related genus, differing chiefly in the lack of oral spines, and 

 brings together the genera Siphodera, Siphoderina, and Paraciyptogo- 

 nimus. 



Mueller and Van Cleave (1932, pp. 114-132) have discussed the 

 family Heterophyidae with special reference to forms occurring in fishes. 

 They state (p. 119) : "Likewise the Crj^ptogoniminae of Osborn (1903), 

 though never previously assigned as a subfamily under the Heterophyidae, 

 is based upon a concept which falls wholly within the Heterophyinae 



