ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 
545 
vegetative functions may be assumed, not only by the floral envelopes, 
but even by the sporophyllary organs, the stamens and pistil. In Ptcrido- 
phytes also ( Onoclea ), the sporophytes cau be made to assume the form 
and function of the foliar organs by cutting off the latter. This trans- 
formation of sporophylls into foliar organs is, in the opinion of the 
author, not a case of reversion, but of an advance of a primary organ 
to a secondary organ of the sporophyte. All evidence shows that the 
sporophyte was, in its early development, entirely dependent on the 
gametopliyte for nutrition. The gradual transference of the assimilating 
function from the gametopliyte to a sporophyte was probably associated 
with a gradual passage from an aquatic to a terrestrial mode of life. 
Heat of Flowers.* — Herr G. Kraus has investigated the extent and 
the purpose of the rise of temperature at the time of flowering within 
the spathe, of various species of Aracese, CvcadeEe, and Palime. In 
Ceratozamia longifolia this elevation takes place only in the daytime, 
the maximum attained being 38*5° C., or 11*7° above the temperature 
of the air. Similar results were obtained with Macrozamia. In the 
Aracese examined the period of maximum elevation is more variable, but 
is never at night. In this order the seat of the elevation is not the repro- 
ductive organs themselves, but the club-shaped appendix to the spadix, 
and it is accompanied by a rapid consumption of starch and sugar. All 
the plants in which this phenomenon occurs are entomophilous, and 
the author regards it as a contrivance for attracting insects to assist in 
pollination. 
Fossil Monocotyledons.f — Mr. A. C. Seward describes some fossil 
plants, chiefly from the Greensand and Wealden, which he refers to 
Monocotylededons, and states his view that we have at present no 
sufficient evidence of the existence of this class of plants before the 
Cretaceous period. 
B. CRYPT OGAMIA. 
Cryptogamia Vascularia. 
Prothalhum and Embryo of Bansea.! — From ati examination of 
Dansea simplici/olia , Mr. G. Brebner states that the genus agrees closely 
with Angiopteris and Maraitia , both in the gametophyte and in the 
embryo sporophyte. One of its chief peculiarities is the occurrence of 
multicellular instead of unicellular rhizoids. The number of antherozoid 
mother-cells of which the antherid is composed is unusually small. The 
growing point of the stem appears to be in a transition stage from a 
single apical cell to a group of equivalent initials. The primary root 
has an apical cell ; but this is not the case with the subsequent adven- 
titious roots, nor with the apical meristem of the cotyledon and of the 
subsequent leaves. The stele, both of the stem and of the root, has a 
distinct endoderm. 
Muscineae. 
Peristome of Mosses.§ — Resuming his researches on this organ, 
M. H. Philibert now describes several anomalous forms of peristome. 
* Ann. Jard. Bot. Buitenzorg, xiii. (1896) pp. 217-75 (3 pis.), 
t Ann. Bot., x. (1896) pp. 205-20 (1 pi.). 
t Tom. cit., pp. 109-22 (1 pi.). Cf this Journal, ante, p. 332. 
§ Rev. Bryol., 1896, pp. 41-56. Cf. this Journal, 1891, p. 73. 
