PROGRESS OF MICROSCOPICAL SCIENCE. 145 



case with the true parasitic plants, which can only manage to put 

 together materials still better prepared, still more nearly approximating 

 to protein, until such organisms are arrived at which are as much 

 animal as vegetable in structure, but are animal in their dependence 

 on other organisms for their food. The singular circumstance observed 

 by Meyer, that the torula of yeast, though an indubitable plant, still 

 floimshes most vigorously when supplied with the complex nitro- 

 genous substance, pepsin ; the probability that the potato disease is 

 nourished directly by the protoplasm of the jDotato plant ; and the 

 wonderful facts which have recently been brought to light respecting 

 insectivorous plants, all favour this view ; and tend to the conclusion 

 that the difference between animal and plant is one of degree rather 

 than of kind, and that the problem, whether in a given case an 

 organism is an animal or a plant, may be essentially insoluble. 



PricMe- cells in the Wall of the Stomach of certain Animals. — In 

 1864 M. Schultze discovered the so-called " prickle-cells " in the 

 mucous membrane of the mouth and conjunctiva, and in the rete 

 Malpighi. A few years later these peculiar cells were found by 

 F. E. Schultze, in the epithelial covering of the lip, of the tongue of 

 the sturgeon, in the skin of Triton niger, Bana esculenta, &c. Now, 

 according to the ' Medical Record,' Joh. Briimmer * has foimd these 

 cells in the first or muscle-stomach, and in the oesophagus of the 

 dolphin, in the stomach of the ox, in the left part of the stomach of 

 the horse, in the stomach of the common rat, house-mouse, water-rat, 

 and field-mouse. The author is of opinion that these cells occur 

 wherever the epithelium of the stomach is hard and like horn, and 

 their formation is proportional to the extent of the corneous process. 

 They seem by their firm attachment to form a fii-m tough epithelium 

 which serves in one place for protection — e. g. in the skin ; in another 

 for breaking up the food — e. g. in the wall of the stomach. 



The Seeds of Collomia coccinea. — A writer, wto signs himself 

 P. J. C, writes as follows to ' Hardmcke's Science Gossip' (February 

 1876) : — " I have received from a friend a few of these very interest- 

 ing seeds ; he gave me these directions to obtain a most curious 

 sight : ' Having obtained your seeds, take a sharp pocket-knife, and 

 cut off as small a quantity as possible of the outer skin, then place it 

 upon your fluid slide, and cover it with a small square glass slip ; at 

 first use your 1-inch object-glass, and it looks like a small piece of 

 dirt, but directly you put the smallest quantity of water in at the top 

 of the slip, so as to touch the seed, myriads of spiracles wall start 

 away from it, and continue so to do for nearly ten minutes. I have 

 tried this experiment a great many times, and always with success.' " 



The Production of the Prothcdlus from the Spore of the Chara. — 

 Herr A. De Bary has published a recent paper on this subject in the 

 ' Botanische Zeitung,' in which he gives a detailed account of the 

 manner in which the prothallus is produced from the spore in 

 the CharfB. That the new Chara-plant does not spring directly from 



* ' Centralblatt,' No. 28, 1875. 



