262 BOLL, ON THE STRUCTURE OP 



valve a smaller uunibcr of since may be counted. Although 

 my opinion may not agree with that of any one of the most 

 distinguished microscopists, I am at present inclined to the 

 belief that the DiatomacecE, like any other organism which 

 is produced from a germ, is born of small size, and grows as 

 it passes through the various stages of life. And I believe 

 that this growth may take place in various ways in different 

 species. But as an inquiry of this kind is ultimately con- 

 nected with the very thorny question of the true limits 

 between the genera, species, and varieties of the Diatomaceaj, 

 I will reserve it for a future occasion. 



On the Structure of the Lachrymal Glands. 

 By Franz Boll. 



Recently, in histological researches, peculiar star-shaped 

 cells have been noticed in the aciniferous glands. Krause 

 was the first man wdio isolated these, in the case of the 

 parotid of a cat, by means of maceration in vinegar. He is 

 inclined to treaty them as nervous organs. Henle also 

 describes stellate cells in the walls of the rennet glands, as 

 well as the parotid and mamma?. He also thinks that they are 

 most likely of a nervous character, although he has never 

 seen any connection wdth the nerve-fibres. Pflueger describes 

 multipolar cells in the salivary glands of the rabbit. He 

 holds them to be multipolar ganglion-cells, and observed on 

 one side their connection with the fibres, and on the other 

 side with the secretory epithelial cells. Finally, KoUiker 

 has made closer researches concerning the cells in question 

 in the salivary glands. He considers them to be simply 

 forms of the covering structure of the alveolus, which seem 

 to him to represent a kind of reticukim. 



I began to give my attention to these doubtful objects 

 whilst examining the lachrymal glands in the summer vaca- 

 tion of 1867, and continued in Btmn later on to do so. 



The lachrymal glands of the pig, sheep, calf, and dog, also 

 the submaxillary of the rabbit, calf, and dog, and the parotid 

 of the cat and rabbit, served me as objects of examination. 

 The following are the methods of isolating these cells :— 

 Maceration in vinegar (Krause); treatnient with bichro- 

 mate of potash (Henle) ; with o3 per cent, liquor potassge 

 (Pflueger) ; and placing in a solution of iodine, later on 



