436 THE AMERICAN NATURALIST.  [Vor. XXXIX. 
7. Proboscis sheath provided with cecal appendages ; proboscis armed 
with central plate bearing a number of stylets besides several pouches 
of accessory stylets °. . DREPANOPHORUS. 
8. Ocelli numerous, extending poitiriody dig lateral nerve cords beyond 
the brain ; basis of central stylet massive, with flattened or concave 
posterior iia i i ZYGONEMERTES. 
8. Ocelli do not extend posietioity TREE bos: basis of central die 
commonly (but not always) rounded posteriorly . 9. 
9. Body usually not very small ; ocelli usually numerous, alway more than 
4 in the known Pacific est species . . AMPHIPORUS. 
9. Body very small; ocelli usually 4, ipd in ioiai, occasionally 
each of the four ocelli-is double or fragmented into groups ; rarely 
ocelli are entirely wanting . : i , : . TETRASTEMMA. 
EMPLECTONEMA. 
1. Dorsal surface green; central and accessory stylets curved ; ini long 
and slender; basis very long ; body dark or pale green dorsally ; whit- 
ish, yellowish, or very pale green ventrally 
E. gracile (Johnston) Verrill, B, A, P, C, Y. 





A B C D E F 
Fic. 1.— Outlines of — oe and bases. 
A,E rare a grac E, rtes albide 
E E. bürger F, 2; thalassina 
E. purpuratum G, Z. virescens. 
DR: gurfnratum. Central stylet more highly magnified. 
