232 



DR. T. S. COBBOLD ON THE PARASITES OF ELEPHANTS. 



clathrate. The tail is obtuse, not so sharp-pointed as in Sclerostoma sipunculiforme, and 

 has the genital organs situate a short distance from the extremity. It is frequently, 

 but not in all cases, convolute. The body of the male is longitudinally striated ; and the 

 bursa at the extremity of the tail is lobed." 



Notwithstanding what I have advanced respecting the clathrate appearance, the fact 

 of my not having examined a female worm of this species will probably leave the question 

 still an open one. As regards the male, the characters of the hood are particularly 

 striking, even more so than they are in Sclerostoma svpu/nculiforme. 



Whilst Dr. Baird's enlarged view of the bursa makes this sufficiently apparent, he has 

 not supplied any description of details. In the hood before us we find two enormously 

 exaggerated divisions of the middle 

 ray (c, c') ; but in Sclerostoma sipun- 

 culiforme we found that most of 

 the rays were of more or less uni- 

 form length and thickness. Here 

 also we have the anterior ray 

 double (a), with its halves closely 

 applied, as obtains in most Stron- 

 gyles ; we have the antero-lateral 

 ray (b) simple and widely sepa- 

 rated from those above and below 

 it ; we have the ends of the huge 

 finger-like divisions of the middle 

 ray (c, c) extending far beyond the 

 terminal points of the posterior 

 rays ; and we have both postero-lateral (d) and posterior rays (e) reduced to within ex- 

 tremely narrow limits. Any one at all familiar with the typical forms of Strongyle bursse 

 cannot fail to see at a glance that the morphological departures here displayed are not 

 merely distinctive of the species as such, but altogether unique in themselves. In this 

 connexion another noteworthy feature relates to the form of the spicules. Neither in this 

 nor in the preceding species do these organs appear to have come under Dr. Baird's ob- 

 servation. Whilst retracted they are not readily visible under the microscope ; however, 

 a strong light, aided by slight pressure, is sufficient to expose them to view. In this 

 species each spicule consists of a shaft which is truncate above and pointed below. The 

 lateral blade-like expansions are unequally developed, the right side being flabelliform, 

 diaphanous, and marked by branching stria?, which proceed from the axis and arc 

 radiantly disposed (PL XXIII. fig. 5). The spicules are of equal size, each measuring 

 Yq of an inch in its long diameter. Immediately above the hood, and in front of the 

 spicule, there is a slight enlargement, which, even in spirit-specimens, preserves a 

 yellowish colour (PI. XXIII. fig. 4). This is probably an unusually large seminal 

 reservoir. 



Concerning the special part played by this and the preceding species in the production 

 of injury to the host, evidences will be produced at the close of this memoir. 



Diagram of the hood and rays of Strongylus claihratus 



( x 24 diam.). 



