576 F. A. E. CREW AND HONOR B. FELL 



Points of interest in connexion with this stud\' are as fohows : 



1. It seems probable that many of tho structures in abnormal 

 testes wliich have been regarded as ova are in reality of a 

 degenerative character, similar to that of the bodies we have 

 described. 



2. The interstitial cells of the rabbit's testis are in certain 

 areas being metamorphosed into what appear to be fat-forming 

 cells. 



3. The colloid degeneration of the spermatic epithehum is 

 correlated with an increased production of white fibrous tissue. 

 This phenomenon may be explained on the assumption that 

 some, or, as in the human, the whole of the colloid percolates 

 through the peripheral layer of cells and stimulates the cells 

 of the basement membrane and of intertubular connective 

 tissue to greater activity. 



EXPLANATION OF PLATES 18-23. 



Plate 18. 



Fig. 1. — Goat. Seminiferous tubule. x470. Stained •with Van Gieson. 

 All the epithelium is desquamated into the lumen to fonn a syncitial mass 

 in which several ovum-like bodies are ux the process of formation. Two 

 complete bodies are seen, the lower one is completely calcified but the 

 centre of the upper one still gives the orange coloration characteristic 

 of colloid. A number of colloid globules are seen in other parts of the 

 lumen. 



Fig. 2. — Cat. Spermatocytes within seminiferous tubules. x 900. 

 Stained Mallory. Shows every stage in the formation of colloid globules 

 by hypertrophy of the nucleolus. In (a) and (c) the cells are centrally 

 situated, m (b) they are peripheral. 



Fig. 3. — Rabbit. Seminiferous tubule, x 470. Stained Van Gieson. 

 Two ovum-like bodies are present surromided by desquamated cells. They 

 show the vivid orange coloration characteristic of colloid. Calcification 

 has not yet set m. The thickened basement membrane is also seen. 



Fig. 4. — Goat. Seminiferous tubule, x 470. Stained Mallory. A single 

 circular body lies within the tubule and consists of a central whitish area 

 surromided by a bright blue rmg. A circle of more darkly-staining 

 granules is also present and the body is invested by a large mass of debris 

 which at one side spreads out into a syncitdum connecting the central 

 bodv with the wall of the tubule. 



