584 



THE TISSUES. 



currence of extravasated blood in various stages of metamorphosis 

 is also so frequent as to be almost regarded as a normal constituent. 

 The vessels will be described further on. The fine trabeculae are 

 also composed of areolar tissue, and are 3 ^ -$ to T5 V^ f an inch in 

 diameter. The minute fibres are very numerous, and of collagenous 

 tissue ; some of them being the terminations of the vascular sheaths. 

 The cells of the pulp (parenchymal cells) (Fig. 411), are round, 

 uni-nucleated, ? ^V^ to 2?W f an mcQ i n diameter, and apparently 



Fig. 411. 



Pulp of human spleen, a, a. Blood-corpuscles. &, 6. Dotted nuclei, c, c. Nucleated vesicles, d, d. 

 Colored masses of hsematine. (Gray.) 



like those of the Malpighian bodies, soon to be described. More 

 than in the latter also, free nuclei are mixed with them. Pale, 

 round, homogeneous bodies also are found, somewhat larger than 

 blood-corpuscles, resembling free nuclei, or homogeneous nuclei 

 surrounded by a delicate investment ; pale larger cells, up to ysW 

 of an inch in diameter, with one or more nuclei and cells with 

 dark cojorless fat-granules. These elements also exist, but in less 

 extent, in the Malpighian corpuscles. The cells are united by a 

 reddish-yellow fluid ; and, together with the latter, constitute about 



