210 Mr Shipley, On a new species of Bothriocephalus. 



My specimens from the intestine of Histiophorus sp. undoubt- 

 edly belong to the sub-family Ptychobothriinae and to the genus 

 Bothriocephalus as restricted by Ltihe. The scolex is unarmed, 

 and provided with longitudinal slit-like depressions which hardly 

 attain the dignity of suckers situated in the dorsal and ventral 

 plane. Laterally and more anteriorly is a still slighter depression. 

 The anterior end of the scolex bears a flat cap something like a 

 cook's cap but with four distinct lobes, symmetrically placed, two 

 right and two left. Posteriorly the head is slightly constricted 

 and then it expands again to terminate in a marked rim. (Fig. 1.) 

 There is no neck. The segments are anteriorly rather funnel- 

 shaped with markedly salient angles. Towards the middle of the 

 body the segments become much broader than long, but quite at 

 the posterior end they lengthen again. The edges of the first 

 six to ten segments which overlap for some distance the suc- 

 ceeding segment are divided up into four lobes but this lobation 

 disappears behind. The posterior border of the last segment is 

 rounded. The salient edges of the posterior border of the 

 anterior segments overlap the succeeding proglottis for almost 

 half its length. 



The head is 1'5 mm. in length and l'4mm. to the constriction 

 mentioned above, its breadth at the anterior end which bears the 

 four-lobed cap is "4 mm. The measurements of the proglottides 

 vary very much in different regions of the body. The longest 

 are those of the anterior third where a length of *3 mm. is attained. 

 Further back the segments shorten and broaden till they acquire 

 the dimensions of about '5 mm. broad by "16 mm. long. 



The ovary lies across the hinder part of the proglottis, and is 

 produced into numerous rounded lobes. The ova are closely 

 crammed together at the periphery but in the centre of the organ 

 in the middle line the ova are more loosely packed and more 

 spherical in outline and have passed into the chamber called 

 the ootype. Their diameter here is some "01 5 mm. Into this 

 region opens the small shell-gland, and the ducts of the yolk 

 glands. The shell-gland lies posteriorly to the ovary between 

 the right and left halves of that organ and with the ducts of 

 the yolk glands it opens into the ootype posteriorly. From the 

 ootype the uterus arises and makes a few turns, coiling right and 

 left and then opens into what the Germans call the "uterushohle" 

 or uterus-sac, a large spherical expansion of the uterus which 

 opens by a very definite pore on the ventral surface of the pro- 

 glottis. The difference between the spherical eggs in the ootype 

 and those in the uterus is striking. The former are much smaller, 

 well stained, with conspicuous nuclei and "015 mm. in diameter, 

 the latter are enclosed in a bright yellow egg-shell of an oval 

 shape impenetrable to staining fluids, 045 mm. long by "035 mm. 



