. Fresh-water biology. Freshwater biology. 720 FRESH-WATER BIOLOGY 134 (''33) Valves tumid in anterior part; post-abdomen narrow. Euryalona Sars 1901. Sole American species Euryalona occidentalis Sars 1901. General form resem- bling KuTzia, but less compressed; no crest. Valves gaping in front, tumid in infero-ante- rior region; marked obscurely with concen- tric lines; dorsal mar- gin arched. Keel of labrum angled behind but not prolonged. Post-abdomen very long, slender, lobed at apex; with about 20 marginal and very fine lateral denticles. Claws straight, armed about as in Campto- $ with st
. Fresh-water biology. Freshwater biology. 720 FRESH-WATER BIOLOGY 134 (''33) Valves tumid in anterior part; post-abdomen narrow. Euryalona Sars 1901. Sole American species Euryalona occidentalis Sars 1901. General form resem- bling KuTzia, but less compressed; no crest. Valves gaping in front, tumid in infero-ante- rior region; marked obscurely with concen- tric lines; dorsal mar- gin arched. Keel of labrum angled behind but not prolonged. Post-abdomen very long, slender, lobed at apex; with about 20 marginal and very fine lateral denticles. Claws straight, armed about as in Campto- $ with strong hook; vas deferens opens on Color dark brown-yellow. Length, 9, to. Fig. 1124. Euryalona occidentalis Sars. cercus. Five pairs of feet; hook on first foot of 9. upper (ventral) side of post-abdomen about middle, mm.; $ mm. Florida, Louisiana, Texas; not uncommon in weedy pools and lakes. ^3S (123) Body not greatly compressed; claws with i basal spine, or rarely none. 136 For all species with two spines on terminal claw, see 171 ft. 136 (168) Rostrum not greatly exceeding antennules 137 137 (167) Rostrum pointed. . 138 138 (150) Infero-posteal angle rounded, without teeth 139 139 (144, 147) Post-abdomen with marginal and lateral denticles. 140 140 (143) Post-abdomen relatively long and narrow; marginal denticles numerous, longer distally. Basal spine stout and long. Oxyurella Dybowski and Grochowski 1894 . 141 In general like Alona. Post-abdomen long, slender; with marginal and lateral denticles, the former numerous and ending in a group of large denticles at angle of post-abdomen. Termi- nal claw straight, with one large basal spine, attached some way distal to base of claw. Color yellow or yellow-brown. This genus is the same as Odontalona Birge. 141(142) 12-is marginal 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 per
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Keywords: ., bookcentury1900, bookdecade1910, booksubjectfreshwa, bookyear1918
