142 Procccdi)i(js of the Roi/al Iris/i Academif. 



the red granules are in reality produced by chan2;e of colour of the 

 green. (Plate 14 ; Plate 15, fig. 2 to the left ; fig. 4.) 



But in the formation of the " contents" yet another granular con- 

 stituent has a part. Besides the ahove-mentioned red and yellowish- 

 green graniJ.es, minute homogeneous-looking rounded little granules 

 occur, of a pale hluish tint. (Plate 14.) 



When -wholly encysted, and now im a completely dormant and 

 quiescent condition, the organism appears yeiy densely filled, and 

 hence the larger examples are quite opaqiie. 



The first and second year of my noticing this organism, in ex- 

 amples from the Co. Westrneath pool, quite fi'equently — since then 

 from that site, as well as Connemara, very rarely — did I succeed in 

 obtaining a view of the condition now to be described. It was there- 

 fore well to have secured the accompanying di-awing, when the ex- 

 amples were readily found in suitable order. 



IS^otwithstanding the seemingly tough consistence of the wall, or 

 envelope, in manipulation, the contents have the power to burst or 

 force their way outwards through it, and the basic plasma pours itself 

 forth, bearing with it the granular contents as described, but not any 

 of these escape or become scattered, for they are held together by the 

 common medium, but, on the contraiy, they pass onwards with it, and 

 soon a remarkable sight presents itseM. The plasma, thus become ex- 

 tended and spread out over a space so much gi'eater than when it 

 occupied the cavity of the envelope, now shows the contained granules 

 mutually much further apart, rendering the hyaline connecting basic 

 medium in itself more apparent. This does not seem to form a border, 

 or any "ectosarc" region; the contained gi-anules stand close up to 

 the outer contour, leaving no hyaline margin. In examples presenting 

 this condition in a well-expressed manner (Plate 14), I think I see 

 yet another constituent of the basic substance, different from the com- 

 mon hyaline matrix — a kind of greenish, plastic, amorphous substance, 

 as it were comparable to "diffused" chlorophyll, seemingly distinct 

 from and yet, as it were, combining at the margins (if one may use the 

 word) of the patches of it, with the hyaline matrix, than which, how- 

 ever, this substance appears to be of a less fluent or yielding natui'e. 

 I do not think it would be capable of detection unless in examples so, 

 as one might say, "on the stretch." ]^ow, a beautiful play of quite 

 globular jyulsating vacuoles is seen to take place in the basic mass ; 

 these vacuoles, though very numerous, never become very largely dis- 

 tended. It is very interesting to watch theii' alternate diastole and 

 systole, now here, now there, distributed all over the extended mass ; 

 but, to see this properly, attention should be confined to a single 

 vacuole. It is curious to observe a vacuole originate in the middle of 

 a layer of the greenish substance adverted to — the vacuole expands for 

 a time in the usual manner, but, as if the expansion took place too 

 vigorously in proportion to the yielding caj^acity of the surrounding 

 substance, the latter becomes somewhat siiddenly, as it were, cracked 

 or split at opposite sides of the globular vacuole, the lift extending to 



