THE MYXOSPORIDJA, OR PSOROSPERMS OF FISHES. 285 



of dark, longitudinal, ecto])lasmic laminae separated by clear, somewhat 

 reddish, apparently semifluid interlaminte. l^ot infrequently there exists 

 a similar clear red<lish boundary layer between ectoplasm and endoplasm 

 (Biitschli). 



Endoplasm consisting of colorless or yellowish myxoplasni, usually 

 tinted reddish to reddish-browu (see Hccmatoidin below); distinguished 

 irom the ectoplasm by its color and by the presence of granules, globules, 

 numerous small nuclei, vacuoles and inclusions (notably htematoidin 

 crystals). Granules minute, arranged without order. Globules num- 

 erous, irregularly scattered; in all probability fatty, being soluble in 

 alcohol ; ^ containing hicnuitoidin crystals. The older writers also 

 include the nuclei under the term globules. 



Nuclei very numerous, small, with a dark surrounding membrane, 

 granular contents, nucleolus and radiating iibrillnB (Biitschli). Pfeiffer 

 remarks ^ that these are to be referred back to the original single 

 nucleus of the young myxosporidium. 



Vacuoles (apparently nonpulsating; indefinite as regards number 

 and position), are sometimes seen in forms with few granules. 



Hoematoidin crystals: These were first observed by Lieberkiihn.' 

 They were subsequently noted by Biitschli,* who rightly remarked 

 that they must be derived from the blood of the host; i. e., that they 

 are of extramyxosporidian origin. They occur in the fiit globules, and 

 are found free in the protoplasm only after solution of these globules by 

 alcohol. They can be found from the smallest beginnings up to a more 

 conspicuous size, the fat-globules then forming a proportionally slight 

 covering for them (Biitschli). 



Pfeiffer ^ describes and figures a red blood corpuscle as included 

 within the endoplasm. This he regards as the source of the ha^ma- 

 toidin crystals. He asserts that they are constantly present and that 

 they occur free or within the fat- globules. He adds that if the myxo- 

 sporidium has amceboidly surrounded these blood corpuscles and now 

 consumes them, then in spite of the structure of the spores the Myxo- 

 sporidia can no longer be regarded as Gregarines. 



Pseudopodia of 2 kinds: (1) Blunt, obtusely rounded, usually 

 formed of ectoplasm alone, endoplasm taking part in formation only 

 where the body as a whole forks. (2) Fine, hair-like or bristle like, 

 usually rigid, frequently branched, comparable to similar processes of 

 many ainoebie, fre([uently covering whole surface, not rarely, however, 

 limited to a certain region of same (e. g., the end, as in certain amoebre) ; 



' Biitschli, Bronn'a Tbier-Reich, 1882, i, p. 594. 



'Die Protozoenals Kiankheitserrop;er, 1890, 1 ed., p. 44, 



'Miiller's Archiv., 1854, p. 350; see also next footnote. 



* Zt8(rl)r, f. wiss. Zool., 1881, xxxv, p. 642; Brouirs Thiev-lJoicb. 1882, i, p. 594. 

 Biitschli credits their discovery to Lieberkiihn and Meissner. I iutVr from Lieber- 

 kiihn's statement, that Meissner's results were coiuuiuuicated to him orally but were 

 not published. 



6 Die Protozoeu als Krankheitserreger, 1890, 1 ed., p. 4G; ib., 1892, 2ed., pp.17, 132. 



