416 
BULLETIN OF THE UNITED STATES FISH COMMISSION. 
Myxobolus?? zschokkei, sp. nov.' 
(Psorosperms of Corey onus fera Zschokke, 1884, Archiv. de Biol, v, pp. 234-5, t. 10, f. 16.) 
Cyst: Oval, pea to nut size; multiple (up to 30). 
Spore: Body lenticular or oval, a little wider in front than behind; often bearing- 
in front a blunt prolongation; posteriorly one distinguishes two “tails” ( queues ) 6 to 8 
times longer than the body, attenuating posteriorly, curved and undulating; the num- 
ber of two “tails” is constant; at the pole opposite to the “tails” are 2 oval, trans- 
parent anteriorly converging vesicles; one sometimes sees, however, an extremely fine 
canal extending from the posterior end of each vesicle to the base of the corresponding 
“ tail” ; the vesicles then probably play here also the role of receptacles for the “ tails” ; 
round retractile globules are also seen at the bases of the vesicles ; the remainder of the 
body is filled by a homogeneous plasmic mass which frequently contracts to the center 
of the body cavity, forming a clearly distinct round or oval mass. 
Habitat : Subcutaneous and superficial intermuscular tissue of Coregonus fera Jur. ; 
April and May. 
Myxobolus brevis ThMohan, 1892. 
Henneguya brevis, Bull. Soc. pliilomat. Paris, iv, p. 177. 
Myxobolus medius Thfilohan, 1892. 
Henneguya media Bull. Soc. pliilomat. Paris, iv, p. 176. 
Myxobolus monurus, sp. nov. 
(Psorosperms of Aphredoderus sayanus Ryder, 1880, Amer. Nat. xiv, pp. 211-212, figs. 1, 2.) 
Cyst: Lenticular, large, about 20 in number. 
Spore : Tailed ; body lenticular or slightly obovate ; tail undivided, thick at origin, 
gradually attenuating, more or less curved, 2 to 3 times as long as body ; capsules 2, 
equal, subparallel. 
Habitat: Subcutaneous intermuscular tissue of A. sayanus from near Woodbury, 
N. J. 
Myxobolus macrurus, sp. nov. 
Cyst : 15 to 20 or more, the size of a pinhead. 
Spore: Plainly dorso-ventrally asymmetric; tailed; body round-elliptic; 10 or 11 
pi long; 6 to 8 pi broad; 4 pi thick. Shell insoluble in sulplpiric acid (cold, concen- 
trated) ; superior valve more convex than inferior ; tail somewhat less transparent than 
shell, completely dissolved by cold concentrated sulphuric acid; almost or entirely in- 
visible in balsam; length 30 to 40 pi, usually much less, the attenuate posterior portion 
being easily, and consequently frequently, broken off; tail separated entirely from 
shell by iodine water. Capsules 2, equal; nuclei ad plur. 4, 2 of them being the peri- 
cornual; vacuole present. 
Habitat: Cysts invariably! embedded in the subcutaneous tissue of some part of 
the head (especially the under surface of the lower jaw) of Hybognathus nuchalis A g., 
from the Neelies River, 14 miles east of Palestine, Texas, November 24, 1891. 
* Dedicated to Dr. F. Zscliokke, of Basel. 
t Among several hundred cysts, one was seen at the hase of the pectoral fin, say 3 mm. 'behind 
the head. 
