THE MVXOSPOKIDIA, OR PSOROSPERMS OF FISHES. 257 



Myxosporiilinm. — The following may refer to tliis stage. To me it is 

 rather obscure : 



Between the tidied spores were fouad in great numbers protoplasmic bodies of tlie 

 size of a blood corpuscle or sniaJler, wliich were ruuiul and contained "semen" 

 (fspores). The protoplasm of these bodies was seminal (?sporigenous). The nucleus 

 was sharply delined and contained several semina (? granules). 



Spore. — Round or oval with a sharj) anterior end; sliell double-con- 

 toured; substance homogeneous, texture reminding one of chitin, unaf- 

 fected by acids and by alkaline hydrates; capsules "2, anteriorly placed; 

 lilaments gradually extruded under the influence of gentle heating. 

 By means of staining with fuchsin or methylen blue performed after 

 warming, there appeared in the spore a sharply deti.ied '' nucleus". Tail 

 single or double, consisting of a substance similar to the shell, thick at 

 its origin, attenuating gradually to its free extremity; shai)e similar to 

 that of the tail of M. psorospermicus as figured by Biitschli.^ 



Micro-chemis'tn/. — Fuchsin and methylen blue stain tlie spores and 

 the extruded capsular filaments, but not the shell or the tail. 



Habitat. — Cysts irregularly distributed in the interstitial connective 

 tissue of the thoracic and intercostal mnscles of Goregonus. Loosely 

 united to the surrounding muscular tissue by spongy connective tissue 

 and easily separable therefrom by its rupture. 



As to the relation of this si^ecies to the next, see next page. 



82. Myxobolus sp. incert. 



Psorosperms of muscles of Coregontis fera, Claparede, 187A, in Lunel's Hist. nat. 

 d. poissons du bassiu du Leman, p. 113. 



Cyst. — Five in number, varying in size from that of a filbert to that 

 of a small walnut. Characters constant. Contents, a milky finid or 

 (from resorption of the more liquid portions) a caseous mass. This 

 fluid or semifluid mass consists of i^sorosperms in great number, with a 

 granular protoplasm between them. 



MyxosporicUum. — This granular protoplasm is without doubt the 

 remains of the anneba at the expense of whose protoplasin, and within 

 which, the psorosperms were formed. Tiie protoplasm in fact contains 

 "vacuoles" (pansporoblasts) which in tlie beginning are destitute of 

 proper walls, but which form the i)oint of departure for psorosperm 

 liroduction. The examination of one fragment of protoplasm is sufticient 

 to show all transitions between the simple vacuoles (pansporoblasts) and 

 the vesicles containing the 2 oval corpuscles [capsules] characteristic 

 of the psorosperm, and a tliird corpuscle, whence will be derived the 

 "blastema" (sporoplasm) which fills theposterior part of the body of the 

 psorosperm. It is only a step from these vesicles to the imperfectly 

 developed psorosperms disseminated througli the protoplasm. These 

 last already show all essential traits of the fully developed psorosperm 



' Bronn's Thicr-Eeich, 1882, i, pi. 38, fig. 16. 

 F C 17 



