ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 
701 
BOTANY. 
A. GENERAL, including- the Anatomy and Physiology 
of the Phanerogamia. 
a. Anatomy. 
CD Cell-structure and Protoplasm. 
Eye-spot.* — Dr. A. Zimmermann gives a review of what is known 
respecting the red eye-spot or “ stigma ” in the lower forms of animal 
and vegetable life. According to Franze and other observers, the 
presence or absence of this structure is not uniform even in the same 
species. As a rule the eye-spots are confined to organisms containing 
chlorophyll ; their number is occasionally more than one, but not often. 
Their function is probably connected with the receptivity of the organism 
for light, but even this is not certain. 
Cilia and Pseudo-cilia.'j' — Dr. A. Zimmermann describes the struc- 
ture of the cilia in the lower forms of animal and vegetable life, accord- 
ing to the observations of the most recent authorities. In cells enclosed 
in a cell-wall their connection with the protoplasmic contents can be 
traced. The structures termed “ pseudo-cilia ” by Correns J are not 
endowed with motility, and are more of the nature of hairs than of true 
cilia. 
Structure of the Nucleus in Mucorini.§ — MM. P. A. Dangeard and 
M. Leger give further details of the structure of the nucleus in various 
Mucorini. It has a nuclear membrane separated from a central nucleole 
by cytoplasm containing but little chromatin ; the nucleole is very dense 
and strongly stainable. In the gametes ( Sporodinia grandis ) the nuclei 
are very numerous, and are imbedded in a reticulate protoplasm. The 
number in each gamete varies from three to seven in Mucor , from twenty 
to fifty in Sporodinia. They are derived from the thallus without divi- 
sion in the sporange. After the contents of the two gametes have united 
to form the zygosperm, the very numerous nuclei are imbedded in an 
exceedingly finely reticulate protoplasm, and are of two kinds, the one 
two or three times as large as the other. At a later period this difference 
disappears, the nucleole is reduced to a simple central dot, and the 
nucleus to a small vacuole. In the mature zygosperm is a large central 
vacuole, or sometimes two eccentric ones, the origin of which is obscure. 
(2) Other Cell-contents (including- Secretions}* 
Absorption-spectrum of Chlorophyll. || — M. N. Monteverde states 
that the absorption-spectrum of living leaves consists of seven bands 
and a terminal absorption ; the order of intensity of the former is as 
* Bot. Centralbl., 1894, Beih., pp. 161-5. f Tom. cit., pp. 169-71. 
X Cf. this Journal, 1893, p. 663. 
§ Le Botaniste (Dangeard), iv. (1894) pp. 4-11 (7 figs). Cf. this Journal, ante, 
p. 486. 
|| Acta Hort. Petropol., 1893, pp. 123-78 (1 pi.). See Bot. Centralbl., lix. 
(1894) p. 239. 
