106 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 



lets ; stylets very slender ; 1-i or 16 probos- 

 cidial nerves ; cerebral sense organs beside 

 brain . . A. himaculatus, -p. 24:1. 



2. Body rather short and stout ; mottled thickly 

 with dark brown dots and Idotches ; stylets 

 dagger-shaped; 5 to 8 or more in each of the 

 two lateral pouches; l)asis barrel-shaped ; 12 

 or 18 proboscidial nerves ; cerebral sense 

 organs large, situated beside brain. 



A. punctatulus, p. 253. 

 eee. Centralstylet considerably shorter than basis, g. 

 g. Central stylet about one-third as long as the 

 remarkably massive basis. 

 1. Body short and rounded; proboscis remarkably 

 large, provided with 10 nerves; stylets 

 short and conical. A. macracanthus , p. 266. 

 gg. Central stylet about half as long as basis. 

 1. Body rounded, rather slender; color of fe- 

 males yellowish orange, obscured in intes- 

 tinal region by dark green ova in breeding 

 season; males yellowish, with white flecks; 

 basis broad, flattened posteriorly; cerebral 

 sense organs in front of brain. 



A. tigrinus, p. 243. 

 ggg. Central stylet about three-fourths as long as 

 basis. 

 1. Body small, slender, rounded ; color brownish 

 witli minute dark brown dots ; 25 or more 

 ocelli ; basis bell-shaped ; cerebral sense 

 organs large, situated close in front of l)rain. 



A.fuhms, p. 280. 

 HH. Body very small ; ocelli usually 4, arranged in rectangle ; 

 occasionally each of the ocelli is double or fragmented 

 into groups ; rarely ocelli are entirely wanting. 



Tetrastemma, p. 287. 

 a. With 4 well developed ocelli ... . . b. 



b. Body not especially firm, somewhat flattened . c. 



c. Without distinct longitudinal stripes of brown on 

 dorsal surface. 

 1. Body 30 to 60 mm. in length; brownish red 

 above, witli median white stripe ; ventral sur- 

 face white ; blood corpuscles red ; without con- 

 spicuous lateral grooves on head . T. bicolor, p . 293 . 



