30 PROGRESS OF MICROSCOPICAL SCIENCE. 



Is there any Connection between the Cells of Glands and the Nerves 

 distributed to them ? — According to some recently-conducted researches 

 on tbis point by Dr. C Kiiiiffer, Pfliiger's well-known view of tbe 

 termination of tbe nerves in tbe cells of the salivary glands receives 

 considerable support. Dr. Klein gives a report in the 'Medical 

 liecord,' in which the following account is given of Herr Kupffer's 

 paper in Max Scbultze's ' Archiv.' * He states that Dr. Kupffer, in 

 support of the assertion of Pflviger, that the nerve-fibres of the 

 salivary gland terminate in tbe cells of the acini, describes the 

 distribution and termination of nerve-fibres in the salivary glands 

 of the larvfB of muscidie, and in those of blatta orientalis. In 

 the former the salivary glands represent two large almost isolated 

 simple cylindrical tubes, each of them consisting of a membrana 

 propria and of hexagonal transparent finely granular nucleated cells, 

 which cover that membrane and line the central canal of the 

 gland. The nerves that provide these glandular tubes come to the 

 glands neither as isolated structures nor as accompanying the duct, 

 but together with the corresponding trachea. These, having reached 

 the gland, surround it by numerous branches, which perforate the 

 propria and ramify between the hexagonal cells. Under a high power 

 (Hartnack, No. 10) they are seen to give off fine pale fibrils, provided 

 with numerous nodular swellings, which penetrate into the colls them- 

 selves. Kupffer takes these minute fibrils to be nerve-fibrils. There 

 are, however, also ultimate branches of the tracheas, which, being filled 

 with air, are easily recognizable as such, and having penetrated the 

 cells, may be followed up to their nucleus. More satisfactory were 

 the observations on the large salivary glands closely attached to the 

 oesophagus of blatta orientalis. Those glands are richly provided 

 with nerves, which form plexuses in the interstices of the lobules. 

 From these plexuses numerous nerve-fibres run to the acini of the 

 gland ; at the point of joining these (acini) they form a conical dilata- 

 tion, in such a way that the connective-tissue sheath of the nerve-fibre 

 becomes continuous with, and the distinctly fibrillar axis-cylinder 

 perforates through the membrana propria of the acini. After the j)er- 

 foration, the individual fibrils of tbe axis-cylinder penetrate the cells, 

 and there they terminate. Under high jDowers (800), it can be seen 

 that most of the fibrils run to the cells lying more inwards. The 

 fibrils do not coalesce with the substance of tbe cells, but are quite 

 distinct from this latter for some distance, while pursuing their course 

 in it. On their way they divide sometimes dichotomously. These 

 nerve-fibrils do not terminate in the nucleus, but run towards a vesi- 

 cular structure, which is imbedded in each of the peripheral cells, and 

 which represents the intracellular termination of the duct. The mode 

 of termination is not finally made out. To demonstrate these relations, 

 it is best to place the fresh oesophagus with the adherent glands on a 

 glass slide, and to expose them to the vapours of perosmic acid in 

 substance for a few minutes, until the object has assumed a brownish 

 colour. The lobules of the glands may then be isolated without diffi- 



* Vol. i\., pint 2. 



