PARASITES OF ELEPHANTS. 223 



precedence. Von Linstow described in 190G Strongylus rectus 

 from Dolichotis patagonica. 



According to Article 36 of the International Law of Zoological 

 Nomenclature, the specific name rectum, 1907, must be rejected 

 and can never be used again. 



This is in complete agreement with the views expressed by 

 Lane. He rightl}' was unable to arrive at the conclnsion that 

 the nematode desciibed by von Linstow belongs to the genus 

 Murshidia, because the original description and figures are A'ery 

 unsatisfactory. Onl^- tlie figure of the male bursa shows any 

 marked resemblance to Murshidia. 



I have been fortunate in having access to a series of cameva- 

 lucida drawings of von Linstow's original material in Berlin 

 Natural History Museum, made by Prof. Leiper and very 

 generously placed at my disposal. Unfortunately, the exact 

 magnification was not noted, and therefore von Linstow's measure- 

 ments are relied upon, as they correspond in proportion to the 

 camera-lucida drawings. 



The mouth capsule is wide, surrounded by a chitinous ring of 

 the shape characteristic of the genus. The oesophagus is short 

 and thick. The excretoiy pore is placed a considerable distance 

 caudad of the oesophagus. The vulva is suiTounded by raised 

 cuticle, specially cephalad. The male bursa is short and the 

 lateral rays are not rugged in outline. The spicules are straight 

 and sharply bent near their terminations, which are bulbous in 

 shape. (For details of measurements see Table I.) 



Habitat. From the African elephant (Cameroon). 



Murshidia hadia Khalil, 1922. (Text-figs. 15-21.) 



Material. — The material consisted of one male and four females, 

 selected from Prof. Leiper's collection of Elephant nematodes. 



Shape of hod)/. — The body of the male is straight, the female 

 tail is slightly bent ventrally. The mule is 18-5 mm. long and 

 tlie female is 24 mm. long. The maximum diameter of both sexes 

 is about the middle, being -67 mm. in the male and -82 mm. in 

 the female. The antero-posterior diameter of the male body just 

 cephalad of the bursa is "55 mm. This is a little smaller than the 

 diameter at the middle of the body. 



Skin. — The cuticle is finely striated at intervals of -009 mm. 



Mouth collar .—This, is well developed and rounded in out- 

 line. It is "05 mm. long and '2 mm. in diameter. It is distinctly 

 separated from the rest of the body by a deep groove. 



External leaf-crown. — Arising from the inner surface of the 

 mouth collar is the external leaf-crown, consisting of forty rays. 

 These rays are longer laterally than ventrally or dorsally. Each 

 rny is narrow and gradually tapers to a point. 



Head papillce. — There are the usual four submedian head 

 papillse. They project freely above the head. Each is sur- 

 mounted by a small knob which, as already mentioned, represents 



16^ 



