136<S.S.438) THE MONONCHS 



I 



Mononchus: Number of Labial Papillae in the Outer Set 



Comparative morphology of the cephalic papilla. The outer set of 

 cephalic papillae is the morphological equivalent of the circlet of cephalic 

 setae often to be seen on other free-living nemas. In harmony with this 

 fact, the submedian papillae of this outer set are sometimes two or three 

 in number to each lip, the numerical and morphological factors harmoniz- 

 ing with the law of arrangement of the tactile cephalic setae of nemas, 

 namely: when six are present one is found on each of the two lateral 

 lines and one on each of the four submedian lines ; when more than six 

 are present the increase occurs first on the submedian lines, the common- 

 est number being ten, one on each lateral line and two on each of the 

 four submedian lines; when the number is in excess of ten the increase 

 is again more commonly found on the submedian lines. Illustrations of 

 this law of arrangement are seen on the heads of many mononchs. The 

 secondary submedian papillae of mononchs are sometimes minute and 

 more or less difficult to detect. 



Method of Hunting 



Senses of Smell and Taste. Obviously mononchs hunt by the aid of 

 some other sense than that of sight, since both they and their prey usually 

 live in subterranean darkness. It is, therefore, exceedingly likely that 

 the nerve endings on the head, terminating in the labial papillae of the 

 inner row, serve as organs of taste and smell, and that it is by the aid of 

 these senses that they trail their quarry. 



Picture these ferocious little mononchs engaged in a ruthless chase in 

 the midst of stygian darkness. We may imagine them taking up the 

 scent of the various small animals upon which they feed, among which 

 almost anything they can lay mouth to seems not to come amiss, and 

 pursuing them with a relentless zeal that knows no limit but repletion. 

 How many acres have their organic balance determined by their millions 

 of prowling mononchs ? 



