. Fresh-water biology. Freshwater biology. 548 FRESH-WATER BIOLOGY Embryos from 85 to 108 yu Echinorhynchus thecatus Linton 1892. Body cylindrical, slightly curved; proboscis curved also. Female 11 to 26 mm. long; width to , anteriorly to mm. in maximum, to i mm. posteriorly. Male 7 to 12 mm. long; width to anteriorly, to in maximum, to posteriorly. Hooks in 24 to 31 trans- verse and 12 longitudinal rows surrounded by prominent collars. Embryos 85 to 108 ix long by 18 to 22 11 broad. (Graybill.) In alimentary canal and body cavity of M
. Fresh-water biology. Freshwater biology. 548 FRESH-WATER BIOLOGY Embryos from 85 to 108 yu Echinorhynchus thecatus Linton 1892. Body cylindrical, slightly curved; proboscis curved also. Female 11 to 26 mm. long; width to , anteriorly to mm. in maximum, to i mm. posteriorly. Male 7 to 12 mm. long; width to anteriorly, to in maximum, to posteriorly. Hooks in 24 to 31 trans- verse and 12 longitudinal rows surrounded by prominent collars. Embryos 85 to 108 ix long by 18 to 22 11 broad. (Graybill.) In alimentary canal and body cavity of Micropterus dolo- mieu, AmUoplites rupestris, Amia calva, and Roccus lineatus. Great Lakes and eastern waters. Fig. 850. Echinorhynchus thecatus. a, hooks from ventral side of proboscis near base; 6, hook from ventral, , concave side of probos- cis; c, hooks from dorsal, , convex side of proboscis. X 150. (After Linton.) Embryos from 115 to 165 /x long. Echinorhynchus salvelini Linkins. Male 7 to 9 mm. long, to mm. broad. Fe- male 10 to 17 mm. long, to mm. wide. Proboscis armed with 26 circular rows of 8 hooks each. Hooks alternate in adjacent rows. Basal hooks 39 to so 11 long; hooks in middle and anterior regions 44 to 68/i long, those with basal processes 83 ii long. Embryos IIS to 165 IX long by 20 to 25 11 wide. From lake trout; Lake Michigan. Fig. 851. Echinorhytichus salvelini. Optical section through anterior region of body. X 60. (After Linkins.) 19 (14) Spines on body at some point at least, usually at anterior end. 20 20 (23) Body tapers regularly towards both ends. Proboscis in line with axis of body. Posterior limit of spines alilie on dorsal and ventral surfaces. ... 21 21(22) Cement glands tubular Polymorphtis'Liihe igii. Fine spines on skin ol anterior body. Just behind the limit of these spines a conspicuous annular constriction. Type species P. mimdus (Goeze) fiom various European water birds. At least one species yet undescribed from
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Keywords: ., bookcentury1900, bookdecade1910, booksubjectfreshwa, bookyear1918
