A NEW INTESTINAL TEEMATODE OP MAN. 387 



dorso-ventral diameters anterior to the acetabulum, and also by a more 

 or less distinct transverse depression in the ventral surface slightly 

 anterior to the acetabulum. The anterior portion thus marked off 

 appears in some specimens almost like a cephalic appendage, an ap- 

 pearance which is heightened by the fact that after preservation this 

 anterior part of the worm is frequently bent sharply dorsad out of line 

 with the longitudinal axis of the remainder of the body. 



The posterior extremity (about one-fifth) of the body also is more or 

 less distinctly differentiated from the remainder by a slight, but rather 

 abrupt shortening of both the transverse and dorso-ventral diameters and 

 also by its darker color, due to tbe extension of the vitellaria across the 

 median field in this portion of the worm. 



The remaining, middle portion of the body, comprising something over 

 three-fifths of its length, contains anteriorly the large and prominent 

 ventral acetabulum, behind which this portion of the body is more or 

 less distinctly marked off into five longitudinal tracts or fields, namely, 

 two lateral fields along each lateral margin, containing the intestinal 

 cseca and the vitellaria, a median field containing anteriorly the coils of 

 the uterus, and posteriorly, the ovary, shell-gland and testicles, and two 

 light colored sub-lateral fields separating the median from the two 

 lateral fields and marking the course of the two main branches of the 

 excretory tracts. 



Dimensions. — Fifteen specimens gave the following measurements in 

 millimeters : 



Length. 



Maximum 

 breadth. 



Maximum 

 thickness. 



Length. 



Maximum 

 breadth. 



Maximum 

 thickness. 



4.25 



1.00 



0.70 



5.00 



1.00 



0.80 



4.00 



0.80 



0.60 



6.00 



1.35 



1.00 



4.50 



1.00 



0.70 



5.25 



1.00 



0.80 



5.50 



1.25 



0.80 



4.00 



1.00 



0.60 



5.00 



1.00 



0.75 



4.50 



0.80 



0.60 



5.00 



1.20 



0.80 



5.80 



1.00 



0.70 



4.00 



0.75 



0.50 



4.00 



0.75 



0.50 



4.25 



1.00 



0.70 









Maximum, millimeters long, 1.35 millimeters broad, 1 millimeter 

 thick; minimum, 4 millimeters long, 0.75 millimeter broad, 0.50 milli- 

 meter thick; average, 4.74-f- millimeters long, 0.99— |— millimeter broad, 

 0.70 millimeter thick. 



Cuticle is smooth and without spines. 



Pigmentation is slight and evenly distributed; the fresh specimens 

 were of a semi-transparent red-gray color and the testicles, ovary, 

 vitellaria and uterus were distinctly visible under a hand lens. 



Ventral acetabulum. — The acetabulum measures from 480 to 520 /* 

 in diameter (about half the maximum transverse diameter of the body) 

 and is situated with its center at just about the junction of the first and 

 second anterior fifths of the body. 



