66 Notes and Memoranda. 



squeezed. Three months before the paralysis the girl had experienced pain and 

 difficulty of moving her neck. On this account she entered the hospital, and in 

 the following night her head fell forwards and paralysis ensued. Her face re- 

 tained its colour and a lively expression ; but her body was like a corpse, and 

 death would have followed had not the diaphragm preserved its action and main- 

 tained respiration. M. Maisonneuve succeeded in replacing the vertebra in its 

 proper situation, and recovery was immediate. To avoid a repetition of the 

 accident an artificial support was arranged for the head. 



GrEOWTH of Spirogyka. — The elegant plants of this genus are universal 

 favourites with microscopists, many of whom will no doubt like to make the 

 experiment suggested by Karsten in his papers on the vegetable cell, which are 

 translated in Annals Nat. Hist. " If a spirogyra be allowed to grow for a con- 

 siderable time in pure water, free from organic compounds and from dead and 

 dying organisms, and its joint cells be observed from time to time, they are found 

 to undergo an unusual increase in length, and sometimes a certain augmentation 

 in width. At the same time the circular (spiral) bands of chlorophyll diverge 

 and become more oblique ; their extremities, which were situated in the vicinity 

 of the septum, or even bent towards its central point, are gradually removed from 

 the septum, .... and at length the chlorophyll bands lose their spiral direction 



and became almost straight But if a small quantity of the mucilaginous 



juices of the same species or of some other conferva be added to the water 

 wherein the starved spirogyra is placed, a new vital energy manifests itself ;" and 

 the result is that transverse septa are found in] the joints, and the chlorophyll 

 bands grow in their true direction. 



Magnus on the Constitution" op the Sun. — Poggendorff" 1 s Annals and 

 Archives des Sciences contain the paper from which M. Magnus remarks that if a 

 little soda is introduced into a non-luminous gas flame, it becomes luminous, and 

 at the same time its heat-radiating power is augmented. The flame must have 

 lost heat by vapourizing the soda, but still it emitted nearly one-third more heat. 

 If a plate of platina was introduced instead of the soda, the radiation was still 

 greater. When a little soda was put on the platina the effect increased, and a 

 still further augmentation of emitted heat occurred if some soda was also intro- 

 duced into the flame below the platina. In the latter case, three times as much 

 heat was radiated as when the flame was employed without any addition. From 

 these experiments M. Magnus concludes that solid bodies radiate much more heat 

 than gaseous bodies, and consequently he thinks that solar heat cannot reside in 

 a photosphere composed of gas or vapours. 



Lieberkuhn on Sponges. — This observer states that when sponges are 

 about to perish they emit prolongations which detach themselves and glide over 

 vacant portions of the silicious skeleton, at the bottom of the 'vessel in which 

 they are kept. The detached portions will be found at the end of a few weeks to 

 have developed silicious needles and vibratile cilia. Dying sponges also separate 

 into fragments that perish, and cannot at first be distinguished from the divided 

 portions destined to live. The latter put forth filaments like actinophrys, and 

 some of them become encysted. Out of the cysts came four or five monads with 

 one whip, which can swim or creep like amoeba;. These objects are not integral 

 portions of the sponge, and similar bodies appear in the eggs of other animals 

 when they are perishing. — Archiv.f. Anat. ; Archiv. des Sciences. 



Pouchet on the Fission oe Animalcules.— -M. Pouchet considers fission 

 much more rare than is generally affirmed. He denies that fissiparity exists 

 among the vorticellids. During twenty years he has never seen it in any vorti- 

 cellid. In some rare cases he has seen two of these creatures soldered together. 

 A more common monstrosity he finds to consists in two individuals at the end of 

 the same stalk, and this he considers has been taken for the closing stage of fissi- 

 parity. Small, free vorticellids, he states, will also give rise to such an appearance, 

 by attaching themselves parasitically to larger ones. 



