CALYCULARIA RADICULOSA CAMPBELL 51 



nuclear reticulum not being clearly visible, and there are a number of bodies, 

 one of which is probably the nucleus, although it is possible that there may 

 be more than one nucleus (Figs. 7 A, B). In a number of cases shortly 

 before the division to form the spermatocytes, there could be seen two minute 

 granules (Figs. 7 B, b), sometimes surrounded by a colorless area and 

 perhaps representing the young blepharoplasts, but the small size of these, 

 and the presence of other granular bodies in the cytoplasm makes one hesitate 

 to assert positively that these really were blepharoplasts, especially as no 

 division stages were found, and the relation of these bodies to the nuclear 

 spindle could not be determined. 



The further development of the spermatozoids, which are unusually large 

 in this species and therefore favorable for study, is on the whole much like 

 that of Pellia. After the final nuclear division a definite cell wall is 

 formed between the spermatozoids, the division not running diagonally, as 

 described by Ikeno for Marchantia, but dividing the cell into two approxi- 

 mately hemispherical ones. (Fig. 7 E, I.) 



In the youngest stages met with (Figs. 7 C, D) the nucleus, which now 

 appears somewhat coarsely granular, was still unchanged in form. The cyto- 

 plasm was often contracted but not always so, and in the cytoplasm, some- 

 times at the periphery, but quite as often near the nucleus, could be seen the 

 blepharoplast (Fig. 7, C, D, b), which was already extended into a delicate 

 band. No cases were found where the blepharoplast showed its original 

 round form. A careful examination of the nucleus at this time shows that 

 it is decidedly flattened in the plane of the division wall between the two 

 spermatocytes, so that it appears oval when seen from the side but circular 

 when viewed from above. 



No signs of any body equivalent to the so-called "Nebenkorper," or the 

 "accessory body" described by Wilson 6 for Pellia could be seen, and such a 

 body is probably quite wanting in Calycularia radiculosa. In a slightly later 

 stage, however (Figs. E, F, G), there could often be seen what appeared 

 like cytoplasm extending beyond the nucleus and connecting with the ble- 

 pharoplast. Strassburger refers to such a structure in his somewhat brief 

 account of Pellia. 



The nucleus now begins to elongate and to increase notably in size, hav- 

 ing the form of an almost homogenous crescent-shaped body when seen from 

 the side. The forward end of the crescent is somewhat more prominent 

 than the posterior end and extends into the cytoplasmic prominence, con- 

 necting with the blepharoplast, the exact limits of which are very difficult 



Wilson, M. Spermatogenesis in the Bryophyta. Ann. Bot, 25, 1911. 



