﻿336 cole. 



The following characteristics may he distinguished in all the Uncinaria 

 recovered from the cases here reported. 



A slight depression in the cuticular layer of the body wall upon the ventral 

 surface 0.5 millimeter posterior to the oral margin. (See PI. I. figs. 1 to 4.1 

 At the center of this depression there is an opening into the body cavity. This 

 corresponds to the position of the excretory pore in Uncinaria diiodenalis. In 

 many specimens this opening is surrounded by a mass of granular matter which 

 can easily be removed with no disturbance of the cuticle at the site of attachment. 

 The granular material may be seen within the mouth of the pore in some of the 

 specimens, apparently being extruded from the body. The cervical papillae are 

 situated upon either side of the excretory pore. The position of the excretory 

 pore is not indicated in the original drawings of "Neoator americanus. 



The specimens collected here do not correspond exactly in size with those 

 collected in America. The extreme measurements for the male specimens are 

 from 7.25 millimeters in length for the shortest found, to 8.5 millimeters for the 

 longest: the shortest female measured 10 millimeters in length, the longest 13.5 

 millimeters. 



The presence of a pair of small, ray-like organs within the caudal bursa of the 

 male (not mentioned in the original description), the constant presence of an 

 enlargement of the bursa adjacent to them, the shape of the dorso-lateral rays and 

 the prominence of the dorsal and ventral lobes of the caudal bursa attract one's 

 attention. 



The caudal bursa of the male consists of two lateral lobes continuous with 

 small dorsal leaflets. Each of the leaflets partly surrounds one of the dorsal 

 rays. (See PI. IT.) Ventrally the bursa presents a slight enlargement just 

 posterior to the point at which it is continuous with the body wall. (PI. II.) 

 The lateral lobes are connected ventrally by a delicate, filmy ventral lobe. (PI. II, 

 figs. 3 and 4.) When the lateral lobes are closely approximated the ventral lobe 

 may frequently be seen folded upon itself with the fold deep between the lateral 

 bursa. (PI. II. fig. 3.) 



The dorso-lateral rays are long, slender and clavate. (PI. II, figs. 3 and 4; 

 PI. IV, fig. 1.) 



Within the bursa, anterior to the ventral rays, a pair of small organs may be 

 seen resembling rays in structure, but more delicate. They are constant in all 

 males. It is rarely possible to see more than one in the same focus, but the 

 specimen may be rotated under the cover glass until both organs may clearly be 

 distinguished. These organs are homologous with the praecaudal papillae of 

 Uncinaria duodenalis. They arise from the large trunks which give origin to the 

 lateral, ventro-lateral. and ventral rays of their respective sides, but anterior to 

 these. By placing the specimen in the position that shows the dorsal rays most 

 clearly, one or perhaps both of the smaller rays may be seen directly opposite, 

 upon the ventral surface, the tips of the rays projecting into the ventral enlarge- 

 ment of the caudal bursa. (PI. I, fig. 3; PI. II; PI. Ill, fig. 1.) 



The spicules terminate in barbed tips and the length of the free ends of the 

 spicules is not constant. Some may terminate within the caudal bursa while 

 others protrude as much as one-half the length of the caudal bursa beyond it. 

 (PI. II, figs. 3 and 4.) 



The following measurements of three female worms illustrate the relation of 

 the distance from the head to the vulva to the total length of the worm : 



No. 1: Length of worm, 11.6 millimeters; distance from head to vulva, 5 milli- 

 meters. Xo. 2 : Length of worm, 10.7 millimeters ; distance from head to vulva, 



