RELATION OF INSECTS TO THE PARASITIC WORMS 63 



Gongylonema mucronatum Seurat, 1916 



This nematode occurs in the adult stage in the mucosa of the esophagus 

 of the Algerian hedgehog {Ermaceus algirus). According to Seurat 

 (1916) its larval stage is found encapsuled in the body cavity of various 

 species of coprophagous beetles, Ateuchus sacer, Chironitis irroratus, 

 Onihophagus hedeli, Gynmopleurus mopsus, Gymnopleurus sturmi, and 

 Geotrupes douei, but there appears to have been some confusion as to 

 the identity of the larvae in question, and further investigation of the life 

 history of this species is desirable (Ransom and Hall, 1917). 



Gongylonema hrevispiculvmi Seurat, 1914 



Seurat (1916), in addition to forms found in different species of Blaps 

 that he considers to be third stage larvae of Gongylonema scutatum, has 

 described as second stage larvae of G. scutatum some larval nematodes 

 found encysted in the abdominal cavity of Blaps sp. and Blaps strauchi 

 in certain localities in Algeria. In a later paper, however (1919), he 

 has expressed the opinion, based upon the morphology of the worms and 

 a knowledge of the mammalian fauna in the region in which the parasites 

 are found, that these larva are third stage larvae and belong to the species 

 G. brevispiculum the adult of which occurs parasitic in the cardiac portion 

 of the stomach of a species of jerboa (Dipodillus campestris). 



Further investigation seems desirable as to the identity of the supposed 

 larvae of Gongylonema brevispicidum, as well as of the other larvae of 

 Gongylonema that have been assigned to various species on a basis of 

 apparent morphological similarities and general considerations. A con- 

 tinuation of the excellent work already done bj' Seurat relating to the 

 larval forms of Gongylonema will no doubt clear up the confusion that 

 now exists. 



Gongylonema neoplasticum (Fibiger and Ditlevsen, 1914) Ransom and 



Hall, 1916 



* 



This nematode occurs in the adult stage in the mucosa of the stomach, 

 esophagus and mouth of the rat. It has been reared experimentally 

 in the rabbit and guinea pig as well as in the rat and mouse. It is of 

 special interest from the medical standpoint because it is commonly 

 associated with and perhaps stands in etiological relationship to gastric 

 carcinoma of rats. Fibiger and Ditlevsen (1914) have proved that cock- 

 roaches (Periplaneta americana, Blatta orientalis, and Blattella german- 

 ica), and a grain beetle (Tenebrio molitor) can act as intermediate hosts. 

 The eggs are passed in the feces of infested rats and if ingested by one 



