1028 KECORD OF CURRENT RESEARCHES RELATING TO 



therefore takes place as in Euglena, at what may be termed the period 

 of encystment, i. e. during the phase of immobility, when the body is 

 entirely destitute of cilia. 



In the next stage, each of the new cells increases in size, separates 

 gradually from its sister-cells, becomes clothed with a delicate cell- 

 wall, and finally entirely covered with vibratile cilia inserted inde- 

 pendently side by side, and uniformly clothing the whole of the 

 surface. It next begins to move about, and at the same time secretes 

 abundance of a gelatinous substance. The cilia then gradually fall 

 ofi" in proportion as the body grows in acquiring its ultimate dimen- 

 sions. Only the single polar tuft of hairs now remains. Beneath 

 this bare surface, at two diametrically opposite points of the equator, 

 a band of bright homogenous protoplasm now makes its appearance, 

 which develops on each side into a fringe of hairs towards the pole. 

 Thus we arrive at the original point of departure. 



At no period of development can the presence of cellulose be 

 determined in the membrane, nor of starch in the protoplasm, other- 

 wise the process of gelatinization proceeds as in the Nostochine^e and 

 Bacteriacese. 



Whether this organism ought properly to be considered as belong- 

 ing to the animal or to the vegetable kingdom is, M. Van Tieghem 

 considers, doubtful, and he adds " in the present state of science this 

 question, to which formerly so much importance was attached, seems 

 to me devoid of interest." 



The name Dimystax (Perrieri) is proposed, to indicate the secon- 

 dary tufts of cilia developed after the first tuft has almost completely 

 disappeared. 



MICEOSCOPY, &c. 



Permanent Microscopical Preparations of Amphibian Blood.* — 



Mr, S. H. Gage says that the very excellent method of drying the cor- 

 puscles of mammalian blood on the slide is not applicable to the much 

 more bulky corpuscles of Amphibia. The corpuscles of the latter are 

 sure to be distorted and seamed in drying, hence various methods of 

 preserving the corpuscles moist have been tried with varying success. 

 The following very great modification of the method proposed by 

 Ranvier in his treatise on histology f has been in use for some time 

 in the Anatomical Laboratory of Cornell University, and has given 

 uniformly excellent results. Preparations made three years ago are 

 quite as good as at first. 



Three or four drops of fresh blood are allowed to fall into 10 cc. 

 of normal salt solution (common salt 750 milligrams, water 100 cc), 

 preferably contained in a high narrow vessel like a graduated glass or 

 beaker. The mixture of blood and salt solution should be well 

 agitated, and then 100 cc. of a saturated aqueous solution of picric 



* ' Am. Nat.,' xiv. (1880) pp. 752-3. 



t 'Traite technique d'Histologie,' i. (1875-78) p. 195. 



