148 Proceedings of the Royal Iri-^h Academy. 



make out any stnicture of the nature of a nucleus in this organism, but 

 in this I have failed. I could neither find a nucleus (as in Amoeba, 

 Paniphagus, Plagiophrys, Diaphoropodon, &c.) imbedded in the general 

 mass, nor in the spindles themselves. The general mass is made up of 

 the structures alluded to, and the spindles appear only as bluish 

 plastic and quite homogenous bodies, as described. 



Foreign incepted bodies, generally, if not always, algte, were not 

 infrequent. Sometimes one can see through even a densely filled and 

 thickly enveloped and hermetically closed-in example the "digested" 

 and defunct remains of perhaps a Cosmarium or Euastrum, &c., or 

 an Oocystis or some such organism. (PL 14). The large example 

 figured shows a brown and dead Cosmarium cucurlita, in another place 

 an Oocystis NaegeUi, equally brown and dead (but the characteristic 

 arrangement of the endochrome not wholly lost), whilst next the ex- 

 ti'cmity has been incepted an as yet scarcely altered example of a new 

 and minute Spirotsenia.* Around this has been consolidated the 

 sarcode mass, which all the time gives off its filamentary tracks and 

 spindles, the Spii'otfenia embedded in its midst. 



Several times I have kept such glorious examples, as that figured, 

 on a gi'owing slide ; after some houi's the ramifications were drawn in, 

 and there remained nothing but a " shapeless" mass sticking partially 

 out of the torn opening of the envelope, or all had wholly disappeared. 

 I never succeeded in dii-ectly tracing it, but there can be no doubt 

 such can wholly retract and again secrete a wall, and completely shut 

 itself up. Indeed it appears probable that an isolated or detached 

 portion of the mass left apart also can so encyst itself — one might 

 almost say indeed that this organism appears to have an abliorrence 

 to remain long icitliout a cyst ; nay, even though seemingly the 

 sarcode portion may not have emerged and offered the grand arbores- 

 cent condition at all, still the contained mass will keep secreting a new 

 coat, and adding yet another lamina to its perhaps ali-eady many strati- 

 fied and much thickened envelope. And so, seemingly, after several 

 egresses, retractions, recoatings, or subdivisions inwardly, and fresh 

 recoatings, are brought about the numerous and manifold, often outre, 

 shapes, in the encysted and dormant state assumed by this organism. 



Anxious to find anything to indicate a reproductive process, I have 

 delayed to biing forward even this so cmde an account of this form ; 

 but in that hope I have failed. The only thing pointing thereto is a 

 ' subdivision of the contents, sometimes noticed, into a considerable 

 number of generally equal parts, sometimes a variation in size is 

 noticeable. (PI. 15, fig. 3.) These ai'e giobulai' in figure, and seem at 

 fij'st to be without any wall. Such, kept for a time on a slide, by-and- 

 by collapse shapeless ; if they had a wall they would not do so. But, 



* Spirota.n\a gracillima (n. s. mihi), very miiitite, linear, exti'emely slender, verv 

 slightly tapering, apices blunt, spiral turns very numerous ; a remarkable form, from 

 its extreme slendemess. Breadth ao^oo to ioooo "> about t-srenty to thirty times 

 longer than broad. 



