622 PROCEEDINGS OF THE NATIONAL. MUSEUM vol. 87 



attempts to demonstrate this in stained material have failed; (3) that 

 connection between basal granules and nuclei has not been demon- 

 strated and if present would be exceedingly difficult to trace among 

 the very numerous fibrils that permeate the cytoplasm in every 

 direction; (4) that connection of endoplasmic spherules to the neuro- 

 motor system has not been seen by others, and Horning's and also 

 Scott and Horning's studies indicate that the spherules are connected 

 with a structurally and functionally different set of organs; (5) that 

 the basal granules ("blepharoplasts") are much more numerous than 

 the endoplasmic spherules ("parabasal bodies") and that there is no 

 comparable spiral arrangement of the two sets of structures; (6) that 

 relationship of both Protociliata and Euciliata to the Flagellata is 

 altogether probable, and it seems perhaps possible that there may be 

 a bit closer relationship between Protociliata and Trichonympha, 

 but comparison of Ciliata and Protociliata is closer and more 

 significant.] 



Noble, 1931, referred to the evidence from Zelleriella, cited by 

 Metcalf, that this genus and its leptodactylid hosts were never in 

 northern continents and so must have passed between South America 

 and Australia by some Southern Hemisphere route, and he demurs, 

 saying, "It may well be, however, that the northern opalinids were 

 not in existence at the time the present southern opalinids were being 

 carried south by whatever species they happened to parasitize at the 

 time" [a sentence whose meaning in this connection I cannot solve]. 



Hegner (1931) reported on August 29, 1930, to the Helminthological 

 Society of Washington that of 10 adult Rana clamitans from JMount 

 Desert Island, Maine, none were infected; that the opalinids are lost 

 during the metamorphosis of the tadpoles, between the stages showing 

 only hind legs and the stages with all four legs evident. Young green 

 frogs could not be infected by mouth or by rectum with opalinids 

 from green frog tadpoles [cf. van Orden and Nelson, 1926]. Opalinids 

 were found in tadpoles of tree frogs [species not mentioned] during 

 all stages of metamorphosis and also in the "young adult" tree frogs. 

 He expresses the opinion that apparently some digestive secretion 

 peculiar to the green frog appears during metamorphosis that renders 

 the rectum of this species unfit as a habitat for opalinids. 



Merrill, 1931, in a lecture before the Washington Academy of 

 Sciences, discussed the relations of Philippine biota to the faunas and 

 floras of Malaysia and Australasia and showed frequent changes in 

 connections between lands in these areas during and since the Pliocene 

 period. These affected the distribution of the opalinids and their 

 anuran hosts and are referred to in the present paper. 



Richardson and Horning, 1931, described, with adequate figures, 

 "mitochondria" in Protoopalina, "together with associated, synthe- 



