No. 2.] THE OVARIAN EGG OF LIMULUS. 199 



It has been pointed out that eggs showing this feature of 

 the body most conspicuously are chiefly those arising in later 

 stages of growth of the parent organism, and therefore grow- 

 ing more slowly. This appears to be owing to the absence of 

 nutritive material, which reveals itself in the very pronounced 

 appearance of the reticulum (PL XIV, Fig. 32), which in eggs 

 of the same size, arising earlier in the history of the animal, is 

 often greatly obscured by the presence of an abundance of 

 amorphous granules. 



Nature of the tnctaplasm. — The yolk-nucleus (PI. XIV, Fig. 

 27), I believe, can be considered as an early stage of the yolk, 

 through which all yolk material passes on its way to become 

 definite yolk spheres. It is often associated with the vitelline- 

 body. Such a case seems to present itself here in the form of 

 the metaplasm surrounding the centrosome and sphere. 



The metaplasm consists of at least two kinds of granules. 

 Some of these granules possess an aiifinity for haemato.xylin, 

 which is evident from their retaining this stain even when fol- 

 lowed with such a powerful stain as acid fuchsin. In picro- 

 carmine these granules show a reddish coloration in marked 

 contrast with other portions of the granular metaplasm. 



Careful examination of a large quantity of material showing 

 these granules in connection with the vitelline-body and centro- 

 some appears to show conclusively that they issue as little drops 

 from the living substance of the cytoplasmic fibers and remain 

 closely adherent to them. This appears to take place most 

 freely when the fibrils are relaxed and in a state of rest. It 

 is evident that where the fibers converge and are most densely 

 packed, the number of these granules would be greatest. There 

 is reason to suspect that these granules may be converted into 

 yolk bodies, or be reabsorbed by the fiber so that no trace 

 of them remains. 



It has been shown that the granules in the cytoplasm of the 

 first stages of the egg show an affinity for chromatin stains, and 

 that later this affinity disappears as the definite yolk is formed. 

 It has also been shown that these stainable granules are more 

 abundant in those eggs which increase rapidly in size, and 

 which may be supposed to be abundantly supplied with nutri- 



