370 FAMILY: TRYPANOSOMID^ 



Forms found in the Body Cavity and Salivary Glands. 



The infections are in most cases purely intestinal ones, thongh the 

 flagellates may sometimes find their Avay into the Malpighian tubes. 

 Occasionally, however, the infection extends from the gut to the body 

 cavity. Zotta (1912 and 1921) described a flagellate infection of Pyrrho- 

 coris aptera, a plant bug. The organism {L. jjyrrhocoris) occurred, not 

 only in the gut, but also in the body cavity and salivary glands, as again 

 noted by Franchini (19226). C. hyalommce, described above, is peculiar 

 in that it occurs in the body cavity of the tick, whence it infects all the 

 tissues of the body, including the salivary glands, but is absent from the 

 intestine. 



Robertson (1912) found flagellates of the leptomonas type in the 

 salivary glands of a plant bug {Leptoglossus memhranaceus), and HoUande 

 (1912) found a form, which was named by him L. emphyti, in the hsemocoele 

 fluid of a hymenopteran larva {Emphytus cinctus), a mere puncture of the 

 cuticle yielding a fluid teeming with flagellates. Glasgow (1914) noted 

 a salivary gland infection in another bug {Peribalus litnbolarius). Working 

 with pentatomid bugs {Pentatoma ornata and P. juniperina), Franchini 

 (19226) stated that not infrequently the crithidia, which inhabited the 

 intestine, invaded the salivary glands. Poisson (1925) has noted that 

 L. naucoridis of the water bug Naucoris macnlatus, though usually con- 

 fined to the intestine, may, in the case of heavy infections, invade the 

 body cavity and internal organs, including the salivary glands. While 

 dissecting a species of Culex in Tonkin, Mathis (1914) noted infection of 

 the salivary glands with a flagellate of the crithidia type. In the case 

 of the plant bugs, it is possible that the flagellates may be developmental 

 stages of some plant parasite, while those in the tick and mosquito may 

 have been derived from vertebrate trypanosomes. 



Roubaud's Genus Cercoplasma. 



While in the Congo, Roubaud discovered a remarkable flagellate in 

 the intestine of Pycnosoma putorium. He (1908) named it L. mirabilis, 

 but subsequently (1911) created the new genus Cercoplasma, in which 

 he placed it, together with other similar forms he had found. It will be 

 seen that, apart from certain large giant individuals, the flagellate shows 

 the usual types of the genus Herpetomonas, and in view of the fact that 

 some of the flagellates ascribed by Roubaud to his genus Cercoplasma 

 lack these giant forms, they will be regarded as belonging to the genus 

 Herpetomonas. Roubaud's flagellate then becomes H. mirabilis (Roubaud, 

 1908). The main features of the flagellate are shown in Fig. 172. The 

 giant forms may exceed 200 microns in length, with a maximum breadth 



