No. 393.] REVIEWS OF RECENT LITERATURE. 751 
tampicana Web. l.c. 939, July, 1898. Per. Philippii Web. l.c. 939, 
July, 1898. Phyllocactus phyllanthus Link. vars. boliviensis Web., 
paraguayensis Web., and columbiensis Web. l.c. 957, July, 1898. 
Besides these descriptions of new species, Dr. Weber makes a 
number of new combinations in nomenclature which are here given, 
with sufficient synonymy only for identification. Anhalonium tur- 
biniforme Web. (Echino, turbiniformis Pfeif.) in Bois’s Dict. d Hort., 
90, June, 1893. Echinocactus latispinus Web. (Echino. cornigerus DC. ; 
Cactus latispinus Haw.) l.c. 467, Sept. 1896. Echinopsis catamar- 
censis Web. (Cer. catamarcensis Web.) l.c. 471, Sept. 1896. chinop- 
sis minuscula Web. (Echino. minusculus Web.) l.c. 471, Sept. 1896. 
Echinopsis obrepanda Web. (Echino. obrepandus Web.) l.c. 472, Sept. 
1896. Echinopsis Schickendantzii Web. (Cer. Schickendantzii Web.) 
l.c. 473, Sept. 1896. Mamillaria pectinifera Web. (Pelecyphora 
acelliformis Ehrenb. var. pectinata Hort.) l.c. 804, Jan. 1898. 
Opuntia cereiformis Web. (Grusonia cereiformis Hort., Cer. Brad- 
tianus Coult.) l.c. 897, May, 1898. Op. spathulata Web. (Pereskia 
spathulata Otto) l.c. 899, May, 1898. Pereskia Amapola Web. 
(Per. horrida Parodi., Per. Bleo Morong) l.c. 938, July, 1898. 
Pfeifera ianthothele Web. (Pf. cereiformis Salm., Cer. ianthothele 
Mony.) Le. 944, July, 1898. CH t 
Fertilization of Cycas. — An important recent paper by Professor 
S. Ikeno,' of Tokyo, Japan, treats of the development of the sexual 
products and the process of fertilization in Cycas revoluta. Inci- 
dentally it throws light on the relationships of the Cycads, but its 
chief interest lies in its bearing on the general problems of cell 
structure and fertilization. 
In the development of the archegonia within the endosperm, Ikeno 
distinguishes three periods corresponding with those which are recog- 
nized in the development of animal sexual products. These are: 
1. A period of division, in which the archegonial cells are differ- 
entiated. 
2. A period of growth, during which the central cell (egg-cell) of the 
archegonium attains a relatively enormous size, its nucleus alone being 
75-120 mikra in diameter. The growth takes place at the expense 
of cells which surround the central cell, their nuclei being actively 
engaged in the formation of granular food substance which is passed 
on into the central cell through pores in the intervening cell walls. 
1 Journal of the College of Science, Imperial University, Tokyo, vol. xii, Pt. iii, 
pp- 151-214; Pls. X-XVII. 
