﻿IX, B. 6 Walker: Morphology of the Adults of Filaria 485 



slightly bulbous head which is flattened anterioposteriorly 

 (Plate I, fig. 1) . The posterior end is straight or slightly curved. 

 It tapers slightly to a bluntly rounded tail which is not bulbous 

 (Plate I, fig. 3) . The lateral lines are not apparent. The cuticle 

 shows exceedingly fine cross striations which vary in distinctness 

 in different parts of the worm. The head bears laterally 2 

 series of tiny papillae. No circumanal papillae are apparent 

 (Plate I, fig. 3). The measurements of the two intact females 

 are as follows : 



Table I. — External measurements of 2 female filarise. 



Measurement. 



No. 1. 



No. 2. 



LenKth ___ _ 



tntn. 

 84.0 

 0.2268 

 0.063 

 0.0567 

 0.044 

 0.729 

 0.21 



mm. 

 81.0 

 0.2268 

 0.058 

 0. 0518 

 0.046 

 0.79 

 0.2 



Greatest thickneBs . 



Diameter of head _ 



Diameter of neck 



Diameter of end of tail 



Distance from head to vulva 



Distance from anue to end of tail - 





Intestinal tract. — The mouth is terminal and minute, and does 

 not appear to be surrounded by any appendages. There is a 

 slight thickening of the cuticle lining the mouth (Plate I, fig. 2). 

 It opens into a long slender oesophagus, which is slightly en- 

 larged posteriorly and which is from 1.13 to 1.34 millimeters in 

 length. It is slightly constricted at its junction with the in- 

 testine (Plate I, fig. 1). The slender intestine, which is of 

 approximately uniform diameter, runs practically straight the 

 whole length of the body to the anus, which opens on the ventral 

 side at a point from 0.20 to 0.21 millimeter from the end of the 

 tail (Plate I, fig. 3). 



Reproductive organs. — The vulva is situated anteriorly on the 

 ventral surface, at a point from 0.729 to 0.77 millimeter from 

 the anterior end. There is a slight protuberance at the opening 

 which appears to be two lipped (labium). The vulva opens 

 directly into the vagina, which is enlarged at its anterior end 

 into a pear-shaped organ (receptaculum seminis) placed more 

 or less obliquely and measuring 0.178 millimeter long by 0.06 

 millimeter broad (Plate I, fig. 1). From the receptaculum semi- 

 nis the vagina extends backward from 6.5 to 6.8 millimeters. 

 At first straight and slender it makes one or two loops just 

 behind the junction of the oesophagus with the mid-gut and 



