254 Mr. W. Nicoll on the 



Spelotrema clav'iforme (Brandes). 



Disfomum clavifonne, Braudes, Avchiv x^aturg. liv. p. 2i7, pi. xvii. 

 fig.l. 



In Pelidna alpina and yEr/ialitis hiaticida there oceun-ed a 

 very large nnmber of examples of a species which 1 am obliged 

 to identify as Distominn clavifonne, Brds., despite its author's 

 unsatisfactory description. Brandes's note on the species is 

 meagre and his figure is erroneous in its most importaut 

 feature. It has Idtherto not been redcscribcd. It has been 

 alluded to, however, by Liibe * and Jagerskiold f, both of 

 whom were much of opinion that the species must be regarded 

 as unidentifiable, except by the author himself. In a foot- 

 note Jiigerskiold advances the supposition that it might be 

 included in the genus Levin-enia { = Spelotrema) and gives 

 an interpretation of Brandes's figure in this light. I 

 previously found occasion to agree with this interpretation 

 and my present discovery shows how correct it is. Ad- 

 mitting its correctness, however, there remain three or four 

 errors in Brandes's figure ; the oral sucker is smaller than the 

 ventral, the posterior testes (=:the genital body) is much too 

 large, and the ova are proportionately far too small. Tlie 

 whole drawing is of a sketchy nature %, so that too mucli 

 weight need not be attached to these discrepancies. 



The majority of my specimens exhibit the typical club- 

 like outline in a marked degree. The anterior and postei'ior 

 parts of the body are always separated by a constriction 

 which occurs about the level of the intestinal bifurcation. 

 The cuticular scales extend exceptionally far back (to the 

 level of the testes at any rate). The length of the body 

 never exceeds '40 mm. and may be as small as "23 mm. 

 Immature specimens were never observed. The maximum 

 breadth (posteriorly) is on an average '\7 mm., while an- 

 teriorly the breadth is usually about "13 mm. As in 

 ^P' pyyi^xsuin, the oral sucker is greater than the ventral, 

 but the difference is here more pronounced. They have 

 respectively an average diameter of "038 mm. and •031 mm. 

 The ventral sucker is at a distance of slightly less than a 

 third of the body-length from the posterior end. The 

 pharynx measures •020-'025 x "OlO-'OLS mm. ; the pre- 

 pharynx is about the same length as the pharynx, but it 

 may be considerably longer or shorter. The oesophagus has 



* Zool. Anzeig. xxii. p. 537. 

 t Centralbl. Bakter. xxvii. p. 739. 



X As witness the representation of tlie uterus as a continuous tube 

 liaviiig neither beginning nor end, 



