GENUS: TREPOMONAS 711 



He,o;ner (1925a) has seen giardias in the black-crowned night heron 

 and the great blue heron in America, and Da Ciinha and Muniz (1922) in 

 Ardea socoi, Gathartis aura, and Nycticorax ncevius in Brazil. 



G. agilis Kunstler, 1882. — This form occurs in tadpoles, but the infection 

 disappears when the metamorphosis into the frog takes place. The tadpole 

 flagellate differs from all other known species of Giardia in the length of 

 the body (Figs. 296, d, and 298). Hegner (1922) notes that structurally 

 it differs in no respect from other species, though Eeuling and Rodenwaldt 

 (1921) described certain differences on account of which they suggested 

 the retention of the name Giardia for this form and the name Lamhlia for 

 others. Hegner gives the measurements of G. agilis as follows : length, 14-4 

 to 28-9 (average 20-0) microns; breadth, 3-5 to 5-1 (average 4-5) microns. 



Encysted forms have not been seen, though Alexeieff (1914) encountered 

 small spherical cysts about 10 microns in diameter in a recently meta- 

 morphosed frog. He supposes the flagellates encyst soon after meta- 

 morphosis of the tadpole, and that the cysts, which he regards as those 

 of G. agilis, escape into the water and are ingested by tadpoles in the 

 following spring. 



The form described by Fantham (1923) as G. xenojji, from the clawed 

 frog, Xenopis Icevis, may be the same species. He also records it from 

 Bufo regularis. 



G. denticis Fantham, 1919.— This flagellate was recorded by Fantham 

 (1919) from the blood and intestine of the South African silver fish {Dentex 

 argyrozona). It is not clear that the flagellates in the blood were not due 

 to intestinal contamination. G. salmonis, recorded by Moore (1922) from 

 trout in America, has been shown by Davis (1923) to be a Hexamita (p. 690). 



G. varani Lavier, 1923.— This form was described and named by 

 Lavier (1923) from the Nile monitor ( Varanus niloticus). The length of the 

 body varied from 15 to 21 microns and the breadth from 8 to 11 microns. 



Genus: Trepomonas Dujardin, 1841. 



This genus was established by Dujardin for a flagellate which occurred 

 in sea-water infusions, and which he named Trepomonas agilis. Klebs 

 (1892) also studied this organism and named other species. The writer 

 and Broughton-Alcock (1924) have seen a form, probably T. agilis, on one 

 occasion as a coprozoic flagellate in the stool of a human being suffering 

 from mucous colitis (Fig. 299). 



The organism is distinctly flattened and is oval in outline. There are 

 two longitudinal grooves on the posterior half or two-thirds of the body, 

 one on one surface and the other on the opposite surface. Sometimes they 

 appear as if they are formed by a folding over of the edge of the body in 



