172 COE 



into the brown color laterally. Sometimes, moreover, the fusion is so 

 complete that only a portion of the full number of transverse w^hitish 

 bands can be found. 



The brown color of body varies from a rather light brown to deep, 

 chocolate brown or sometimes deep reddish brown. The whitish in- 

 termediate spaces are caused by absence of brown color, and are not 

 due to any special pigment. 



The ventral surface is commonly dull grayish with a tinge of yellow- 

 ish in median line, but there are often numerous fine granules of 

 brownish pigment scattered over the surface. The colors of the dorsal 

 surface show through to some extent, and in the second variety the 

 brown color often encroaches on the ventral surface and shades off 

 gradually toward the median line. When full of ripe ova, the ventral 

 surface of the intestinal region shows a broad lateral band of dull 

 greenish tint due to the olive green color of the ova. 



Ocelli, — The four ocelli are of medium size and, as usual, are 

 arranged nearly in the form of a square (text fig. 21), although in ordi- 

 nary states of contraction of head there is rather more space between 

 the two ocelli of the same side than between those of either the ante- 

 rior or posterior pair (p1. xiv, figs. 7, 8). Moreover, the ocelli of 

 the posterior pair often seem to be slightly farther apart than those of 

 the anterior pair. 



Proboscis. — Proboscis sheath reaches end of body as in related 

 species. Proboscis pale flesh color, of large size as compared to body 

 of worm. Basis of central stylet about two and one-half times as long 

 as broad, somewhat elliptical, of nearly equal diameter throughout, and 

 only a little wider posteriorly than near the attachment of stylet (p1. 

 XX, figs. 7-9)* Posterior half of basis appears granular and dark, but 

 becomes gradually lighter anteriorly until the anterior third is as trans- 

 lucent as in other species. Central stylet slender, about two-thirds as 

 long as the basis. Each of the two pouches usually contains two acces- 

 sory stylets. Measurements average about .05 mm. for the length of 

 the central and largest accessory stylets, while the basis is about .07 

 mm. long and .025 mm. in average diameter. The proboscis is usually 

 provided with nine nerves, although in a single specimen there was an 

 indication of a tenth nerve. 



Internal Organization. — The dark pigment of the dorsal surface 

 of the body is situated among the epithelial cells of the integument, 

 and extends upward among the cells well toward the surface. 



Voluminous cephalic glands situated both above and beneath the 

 rhynchodaeum reach back nearly to the brain. 



