THE MYXOSPOEIDIA, OR PSOROSPERMS OF PISHES. 



281 



of coagulants, as an irregular, very low and biconcave- excavated 

 cylinder. Lutz could find no true nuclei, either before or after develop- 

 ment. Micrococcus-like corpuscles (similar to those in the ectoplasm, 

 see above) were present, but on account of their inconstancy, these must 

 be regarded as jilasmatic secretions. 



Exit of sporoplasm. — N"ever observed, prolonged immersion in water 

 produfing only a gaping of the valves, with or without a falling out of 

 the capsules. 



Habitat, etc. — Gall-bladder (free-floating in and escaping with the bile) 

 of Bufo agua (toad) in every one of 50 half- grown to grown individuals 

 taken at the most various times at one locality in Brazil ; parasites 

 mostly multiple, sometimes as many as 50; also in young specimens 

 of Gystignathus ocellatus (toad) from 2 localities in Brazil. On the 

 contrary they were absent from 2 large individuals of Brtfo agua from 

 other provinces of Brazil. They were also absent from all the tadpoles 

 examined and from metamori)hosed toads from several localities. 



Effects. — The myxosporidia observed ax)peared in nowise to impair 

 the histological integrity of the gall-bladder. 



98. Cystodiscus ? ? diploxys Gurley, 1893. PI. 42, figs. 11-13. 



Gysi. — Spherical, 12 to 15 (in 1 individual •!) in number, 230 to 400 /v. 

 Membrane rather thick. Contents rounded masses composed of fine 

 brownish granulations suspended in a viscid homogeneous liquid. In 1 

 cyst (pi. 42, fig. 12) the parasites were mixed with numerous fat-like 

 globules, insoluble in caustic soda ; coloring wine red with iodine. 



Spore. — Grreatly resembling the "psorosperms" of fishes; elliptic or 

 slightly flattened, traversed by a ridge apparently marking the line of 

 valve junction. Sometimes showing 2 small brilliant twin grains placed 

 at one of their extremities, sometimes 4 grains disposed in pairs at the 

 2 "ends"; not visibly affected by concenti-ated alkalies or feeble acids; 

 becoming brilliant and homogeneous in salt water. 



Habitat. — In the free state or inclosed in great spherical cysts in 

 the abdominal cavity of the butterfly of Tortrix viridana (an insect). 



