. Fresh-water biology. Freshwater biology. 21 (17, 18) Genital hooks more than 32 in number. P. (Polystomoides) megacotyle Stunkard 1916. Body to by to mm. Genital coronet 36 to 42 equal hooks. Caudal suckers large, crowded. On caudal disc one pair of great hooks, mm. long, one pair of intermediate hooks, mm. long, and small hooks mm. long. From mouth cavity of Chrysemys mar- ginala; Creston, Iowa. Fig. 656. Polystoma megacotyle. Ventral view. X 12. (After Stunkard.). 22 (16) Genital hooks unequal in length. P (Polystomoides) oMongum Wright 1879. Up to m
. Fresh-water biology. Freshwater biology. 21 (17, 18) Genital hooks more than 32 in number. P. (Polystomoides) megacotyle Stunkard 1916. Body to by to mm. Genital coronet 36 to 42 equal hooks. Caudal suckers large, crowded. On caudal disc one pair of great hooks, mm. long, one pair of intermediate hooks, mm. long, and small hooks mm. long. From mouth cavity of Chrysemys mar- ginala; Creston, Iowa. Fig. 656. Polystoma megacotyle. Ventral view. X 12. (After Stunkard.). 22 (16) Genital hooks unequal in length. P (Polystomoides) oMongum Wright 1879. Up to mm. long and mm. wide. Caudal suckers mm. in diameter. Large hooks on caudal disc mm. and small hooks mm. long. Genital coronet of 32 hooks, alter- nately large and small, with free end sharply curved. From urinary bladder of Aromockelys odoralus; Canada. 23(15) Great hooks of caudal disc reduced in size or absent 24 24 (25) Genital hooks 16 in number. P (Polystomoides) orhiculare Stunkard 1916. Length to mm.; width to mm. Caudal suckers mm. in diameter. On caudal disc only a single minute hooklet mm. long, in the base of each sucker; no large hooks. Genital coronet of 16 equal and similar hooks. Egg spherical, to mm. in diameter. In urinary bladder of Chrysemys mar- FiG. 657. Polystoma orbiculare. Extended. Ventral ginala and Pseudemys scripla; North view. X 10. (After Stunkard.) Carolina, Illinois, Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original Ward, Henry Baldwin, 1865-1945; Whipple, George Chandler, 1866-1924. joint author. New York, John Wiley & sons, inc. ; [etc. ,etc. ]
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Keywords: ., bookcentury1900, bookdecade1910, booksubjectfreshwa, bookyear1918
