262 REPORT OF THE COMMISSIONER OF FISH AND FISHERIES. 



form, becoiuinj;' globular or more or less ellipsoidal. It is important to 

 note that in some individuals the entire protoplasm is transformed, 

 changing- from globular and yellow to spongy and colorless, the several 

 globules disappearing almost in an instant, changing directly into clear 

 lu'otoplasm, not growing smaller, as migiit be tliouglit. This shows 

 liow rapidly the pvotopla.sm may change its constitutio!i. ^N^ucleus not 

 found either in fresh material or in tliat treated by hydrochloric or 

 acetic acid. Anilin stain.s only show here and there deei)er colored 

 granules, which, however, could not have the signification of nuclei. 



Kelative to the nuclei, Thelohau, however, says: 

 , In the myxosporidium of Cli h>roiiiyxum leydU/ii, as in the other forms, I have heeii ahle 

 to pi-ove the presence of numerous nuclei; they, are, indeed, of rather small size, but 

 nevertheless are easily recognized in sections, and if, as is probable, Minu;azziui did 

 not observe them, he did not have recourse to this method. 



'■'■Gregarhwid forms.'''' — In some gall bladders of the plagiostomes, 

 Mingazzini found in summer also other forms of a very different figure, 

 which were often united to the myxomycetous forms. These forms were 

 uniformly cyliudric elongate, with one end obtusely rounded and the 

 other drawn out to a sharp point in the form of a long tail four or five 

 times as long as the body, sometimes multiple. Size varying greatly: 

 no very small ones seen ; large ones equaling the size of adult myxospo- 

 ridians. Movements rather rapid, always taking place blunt end fore- 

 most. Protoplasm hyaline, or showing round hyaline globules arranged 

 in regular longitudinal rows. Many contain a subcentral nucleus. 

 Anteriorly the ])rotoplasm contains rather numerous small, strongly 

 refracting granules. This form thus resembles a monocystid Gregarine, 

 but possesses peculiarities which differentiate it therefrom. For, first, 

 an external membrane is wanting, as shown by negative microscopic 

 investigation and by the protrusion (in individuals kept for many 

 hours on the slide) from the blunt end of thin pseudojiodia, which 

 bear a great resemblance to those emitted under the same conditions 

 by the MyxoHporidia; and, second, no known monocystid possesses 

 such a whip-like tail. Besides these forms others occur, which, Avhile 

 resembling in figure the preceding, have their protoplasm more or less 

 charged with yellow granules resembling those of the adult Mi/.wspo- 

 ridia. Between these and the Myxosporidia are found other forms 

 depaiting for the most part by more profound alterations of form from 

 the first ones. Further, the more advanced gregariuoid forms, which 

 possess refracting hyaline globules, take on the character of more 

 adult forms, transforming their hyaline globules into yellow globules. 

 From what precedes we thus see that the gregannoia forms arepluises in 

 the development of the mi/xosporidia of the plagiostomes [italics his own]. 



Commenting upon this view, after noting that Mingazzini remarked 

 that these views of the development of the Myxosporidia (i. e., via the 

 "gregarinoid forms") did not acicord with those held by Lieberkiihn and 

 Balbiani, Perugia' says that his own observation of the exit of the 



I Boll. Scientif., J'avia, 1890, xii, pp. 138, 139. 



