108 SUMMARY OF CURRENT RESEARCHES RELATING TO 



at 39° C. This medium is composed of plasma derived from the animal 

 or the parent of the animal, from which the culture material is to be 

 obtained, but no particulars of its preparation arc given. 



In the first communication, Burrows describes Ins experiments with 

 chick embryos. The myosornes, neural tube, heart and epithelium were 

 dissected upon the warm stage of a binocular Microscope at a tempera- 

 ture of 39° C. The tissues were then kept in plasma in a sealed 

 chamber at this temperature. Mesenchymatous cells began to grow and 

 multiply after an interval of 2 to 12 hours. Long nerve-fibres developed 

 in 3 or 4 hours. The heart continued to beat for 8 hours, and from 

 portions of exposed surface of heart-muscle grew mesenchymatous cells 

 and muscular cells which contracted ;it the same rhythm as that of the 

 adjoining heart. From the central nervous system cultivations were 

 also made, which grew more slowly. 



Further communications deal with the cultivation of adult tissues. 

 The authors have been successful in obtaining growth with artificial 

 cultures of conjunctiva, cartilage, bone-marrow, peritoneum, vascular 

 endothelium, kidney, thyroid, suprarenal, ovary, and lymphatic glands. 

 The abundance and rapidity of growth vary according to the nature of 

 the tissue, the age of the animal, and a number of other factors. The 

 material was obtained from dogs and cats. In cultivations of thyroid 

 from a kitten a few hours old, growth was observed within 12 hours. 

 Cartilage, conjunctiva, and peritoneum grew more slowly. The begin- 

 nings of growth were marked by the appearance of fine granulations at 

 the periphery and upon the upper surface. Each organ produced two 

 types of cell — the connective-tissue cell and the differentiated cell. 

 Detailed accounts are given of the cultivation of renal tissue, spleen, 

 and bone-marrow. With the thyroid gland, the authors have succeeded 

 in producing secondary and tertiary subcultures. 



Further, from sarcoma in the chick and in man, cultures have been 

 obtained. These grew even more rapidly than normal tissues in arti- 

 ficial culture. By means of continuous observations, the process of 

 multiplication of sarcoma cells in vitro has been observed. 



J. Jolly,* criticising the above research, considers that the authors 

 have only demonstrated the survival of animal tissues, a phenomenon 

 already established by previous researches. He is doubtful as to 

 whether any true cultures have been obtained, and even regards some of 

 the phenomena described as in reality necrobiotic changes. 



Modified Method of Isolating Typhoid and Paratyphoid Bacilli. | 

 0. Mayer has made extensive use of a modification of the Lentz-Tietz 

 method. Six loopfuls of the fasces to be investigated were spread on a 

 malachite green agar plate, and then the same glass spreader was rubbed 

 over three large plates of lactose-litmus-agar or fuchsin-agar. The 

 malachite green plate was incubated for 24 hours at 37°, the other plates 

 for 48 hours at 30° C. After this incubation, the growth upon the mala- 

 chite green plate was washed off with a small quantity of saline. This 

 emulsion was allowed to stand for five minutes, and then one loopful was 



* C.R. Soc. Biol. Paris, lxix. (1910), pp. 470-3. 



t Centralbl. Bakt., lte Abt. Orig., lvi. (1910) pp, 552-75. 



