403 DR. E. KLEIN. 



the more characteristic forms of these giant nuclei examined 

 in the perfectly fresh state on the warm stage. Those in 

 figs. 2, 3, and 6 show the basket-shaped arrangement of the 

 intranuclear network. Figs. 4 and 7 are probably dividing 

 forms. Fig. 7 had been observed on the warm stage, and it 

 showed slight amoeboid movements. 



The large thickenings, nucleoli, in figs. 2 and 3 contain 

 vacuoles just like some of the broader trabecules of the 

 network. 



The interstitial or interfibrillar substance of the intra- 

 nuclear network is, in the fresh state, quite homogeneous, but 

 not fluid, as can be readily ascertained by applying pressure 

 to the preparation. The limiting membrane becomes then 

 indistinct, and the nucleus, as a whole, greatly flattened ; 

 the parts of the reticulum are then seen embedded in a 

 distinct homogeneous matrix, the refractive power of which 

 is higher than the fluid menstruum, but lower than the 

 reticulum. After hardening bits of tail in chromic acid (-^ 

 per cent.) or picric acid (two or three parts of saturated 

 solution of picric acid and one of water) and staining the 

 sections in carmine or haematoxylin, the interstitial substance 

 appears slightly stained in some, more deeply in others. In 

 the first instance, the intranuclear network appears in all 

 its delicate details ; in the latter, it is difficult to ascertain 

 the fibrils of the network, and sometimes it even looks as if 

 it were altogether absent, the whole nucleus being composed 

 of a uniformly and deeply stained interstitial substance. 



If bits of tail be treated with osmic acid (especially in the 

 shape of a mixture with picric acid), and the sections be 

 stained in hsematoxylin, the interstitial substance appears 

 uniformly and finely granular, and hence greatly interferes 

 with the distinctness of the network. 



The epithelial cells lining, or, rather, filling the large 

 saccular or tubular glands situated in the tissue of the tail 

 and opening by means of a very narrow canal through the 

 epidermis on the free surface, are of a very huge size, and of a 

 nature different from what they have been represented by 

 Leydig (' Archiv f. mikr. Anat.,' Band, xii., p. 210). This 

 observer describes them (of CoeciUaa.ndiSala7ncmd7'a maculosa) 

 as composed of (a) the cell proper, viz. a protoplasmic 

 portion containing the nucleus, and {b) a frothy excretion 

 attached to the former; the cell proper is placed against the 

 membrana propria of the gland sac, whereas the latter is 

 directed towards the duct. 



I find the cells filling the gland-sacs in the tail of newt 

 considerably differing from this description. In some glands 



