TWO DISTOMES. 



L. B. SEELY, 





 HAVER KORD COLLEGE. 



i. PNEUMONGECES COMPLEXUS, N. S., a NEW FROG DISTOME. 



This description is based on the examination of several pre- 

 served specimens which were received from North Carolina 

 marked " From the mouth of Rana pipicns." 



F. coinplexus is a rather elongated worm, between 5 mm. and 

 8 mm. in length, and in the widest portion, about 1.7 mm. wide. 

 The thickness is about .71 mm., a cross-section being elliptical 

 in outline. The widest region is just forward of the middle, and 

 from here it tapers very slightly toward the hinder end, which is 

 rounded and blunt. Toward the forward end it tapers more 

 rapidly, sometimes giving the worm almost the appearance of 

 having a neck. The oral sucker is subterminal and .4 mm. in 

 diameter. The acetabulum is 2.4 mm. from the anterior end of 

 the animal and very slightly smaller than the oral sucker, being 

 .38 mm. in diameter. Both suckers are sessile. All the speci- 

 mens examined were smooth, /. e., without spines. This may 

 have been due, however, to maceration. Of the five species of 

 this genus described by Stafford (1902), all are covered with 

 spines except one, P. longiplcxns, which is smooth. The deter- 

 mination of this point with respect to P. complc.vns will depend 

 finally upon the examination of a living or freshly-killed speci- 

 men. In the specimens examined, however, there were patches 

 where the cuticle seemed to be intact. It was very thick and 

 there was no trace of spines. Thus the evidence seems almost 

 conclusive that the worm is a smooth one. 



The mouth is easily discernible in the center of the oral sucker, 

 and leads to the muscular, bulb-like pharynx. The oesophagus 

 is about .5 mm. in length. It then branches, forming the two 

 intestinal caeca, which extend to within .4 mm. of the posterior 

 end of the body. The caeca are rounded tubes about . 1 5 mm. 

 in diameter, and are without branches. 



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