and Laboratory Methods. 1505 



stomach gave very interesting results. The stomach of a cat was cut com- 

 pletely across in the middle, and a junction was made between the fundus 

 and the jejunum, so that the pyloric region was entirely excluded from the 

 route along which the food passed. A similar operation was performed 

 on a dog, and both animals were killed about seven months afterward. 

 A careful study was made of the histological changes that occurred in 

 the region of the fundus near the line of juncture. Near the junction with the 

 intestine the fundus glands became more sinuous, the lumen increased in size, 

 and the interglandular tissue became infiltrated with leucocytes. The character 

 of the gland cells was markedly altered. The parietal cells disappeared entirely ; 

 the chief cells lost their characteristic granulation, their basal differentiation 

 disappeared, and they assumed the principal features of the cells of the neck. 

 Both in general structure and in the character of the cells the fundus glands 

 near the new pylorus became strikingly similar to the ordinary pyloric glands. 

 This working over of the fundus glands into glands resembling those of the 

 pyloric region in response to the new environing conditions imposed is a feature 

 of considerable theoretical interest. There is a closing section on deductions 

 concerning the process of secretion in general. s. j. h. 



Conklin, E. G. Centrosome and Sphere in the This paper is a summary of a more 

 Maturation, Fertilization, and Cleavage of ^ i i i i- ^' i • ^ -n 



Crepidula. Anat. Anz. 19: 280-287,1901. extended publication which will soon 



appear in the Journal of Morphology. 

 In fertilization there is no " quadrille " of the centers. The o.^'g sphere and 

 sperm sphere, however, fuse into a granular mass. Within this mass the centro- 

 somes of the first cleavage spindle arise apparently independently of each other. 

 The author holds that " there is good evidence that the cleavage centrosomes 

 are not derived exclusively either from a sperm centrosome or from an egg 

 centrosome, but that one of these comes from the egg sphere, the other from the 

 sperm sphere." s. j. h. 



Hoffmann, R. W. Ueber das Orientiren und ^j^jig ^j^g consistency of yolk depends 

 Schneiden mikroskopisch kleiner, undurch- ■' ■' ^ 



sichtiger und dotterreicher Objecte. Zeit. tO a certain extent upon the fixing fluid 

 wiss. Mik. 4 : 443-448, 1901. employed, the length of time the object 



remains in alcohol and the duration of the process of embedding in paraffin were 

 not found to have any influence on the ease with which yolk can be cut. No 

 reliable method of treating yolk so as to be cut easily in paraffin was hit upon, 

 so resource was had to embedding in celloidin. In orienting small opaque objects 

 in celloidin, 90 per cent, alcohol is a serviceable medium in which to operate, as 

 it enables one to see easily the configuration of the object, and only hardens the 

 celloidin very slowly ; 100 per cent, alcohol, which the author at first employed, 

 dissolves the celloidin too much, and 85 per cent, alcohol hardens it too rapidly. 

 After the object is oriented under a small amount of the alcohol it is placed in 

 xylol to harden. The turbidity that appears after treatment with xylol soon dis- 

 appears, and the mass becomes clear. One convenient method of orienting is as 

 follows : A number of objects are impregnated with thick celloidin solution in a 

 shallow glass dish, enough celloidin being used to form, after it is hardened, a 

 mass but little thicker than the objects embedded. After the mass is hardened 

 under 80 per cent, alcohol it is cut up into small, square pieces, one for each 

 object. After being placed for some time in 90 per cent, alcohol, the objects 

 are stuck to a block, oriented under a small amount of 90 per cent, alcohol, and 

 then placed in xylol until hardened and cleared. s. j. H. 



