NEW SPECIES OF tESOPHAGOSTOMUM. 



465 



apposed to each other to the rim of the bursa. The postero-lateral 

 and medio-lutei'al rays are also equal in size, and pass to the edge 

 of the bursa closely parallel to each other. The externo-iateral 

 ray diverges from the other lateral rays, so that eventually its tip 

 is about one-third of the distance between the medio-lateral and 

 latero-ventral rays. From the main trunk of the dorsal ray, about 

 half-way between its root and its bifurcation, the externo-dorsal 

 ray takes its origin ; it also passes into the lateral bursal lobe, 

 but terminates a short distance from the margin of the bursa. 

 The dorsal ray supports the median lobe of the bursa. Its base 



Text-fiirure 5. 



a — spicules in situ. B. = bursa; Fl. = spiculav flange ; G. = giibernacuhim. 

 b = side view of gubeniaculuui. 



is stout and about 56 //. in diameter, but after the origin of the 

 externo-dorsal ray it is only about half this breadth. It is about 

 230 jn long and bifurcates at its middle, and each branch so 

 formed bears on its outer margin a short, somewhat elbowed 

 branch which is slightly thicker than the I'est of the main 

 branch. 



The spicules (text-fig. 5 a) are long and tubular, and are 

 protruded some considerable distance in almost all the males 

 obtained. They are similar and of equal length, measuring 

 1-29 mm. long, more or less straight, and both end in a sharp point. 



