262 REPORT OF THE COMMISSIONER OP FISH AND FISHERIES. 



form, becoiniii,!;' globiilav or more or less ellipsoidal, [tis important to 

 not(> that in some individuals the entire ])rotoplasm is translbriiied, 

 ciiangin.:;- from globular and yellow to s[)()ngy and eolorles.s, the sevn-ral 

 globules disappearing- almost in an instant, changing directly into clear 

 ])rotoplasm, not growing* smaller, as might be thought. This shows 

 how rapidly the proto])lasm may change its constitution. Xucleus not 

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

 acetic acid. Anilin stains oidy show here and there deeper colored 

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

 Relative to the nuclei, Thelohan, however, says: 



In the inyxospoiidiuiiiofC/(/o?'ow]y.rHwZ('i/rfj(yti, as ill the other forms, I have bctMi able 

 to prove the presence of numerous nuclei; they are, indeed, of rather small size, but 

 novertlieless are easily recognized in sections, and if, as is pro);ablc, Mini!,;fxzini did 

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



" Gregarinoid forms.''^ — In some gall bladders of the plagiostomes, 

 ISIingazzini found in summer also other forms of a very ditiereut figure, 

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

 uniformly cylindric elongate, Avith one end obtusel}' rounded and the 

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

 times as long as the bod}^, 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 snbcentral nucleus. 

 Anteriorly the i)rotoplasm contains rather numerous sinall, strongly 

 refractiu g- gran ules. This form thus resembles a mouocystid G regarine, 

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

 an external membrane is wanting, as shown by negative microscopic 

 investigation and by the i)rotrusiou (in individuals kept for many 

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

 bear a great resemblance to those emitted under the same conditions 

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

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

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

 charged with yellow granules resembling- those of the adult Myxoxpo- 

 ridia. Between these and the Myxosporidia are found other forms 

 departing for the most part by more i)rofound alterations of form from 

 the first ones. Further, the more advanced gregarinoid forms, Avhich 

 possess refracting hyaline globules, take on the character of more 

 adult forms, transforming, their hyaline globules into yellow globules. 

 From Avhat precedes we thus see that the greyarinoM forms are phases in 

 the dei'elopincni of the my.vosporidia of the plagiostomes [italics his own]. 



Commenting ni)on this view, after noting that Mingazzini remarked 

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

 "gregarinoid forms") did not accord with those held by Lieberklihn and 

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



Boll. .Scioiitir., Pavia, IS'JO, Xli, pp. 138, 139. 



