164 BOTANICAL GAZETTE [FEBRUARY 
Parthenogenesis in Bennettites.—Parthenogenesis, or the development of 
an embryo from an egg without fertilization, has been demonstrated for several 
angiosperms, and is claimed for Pinus pinaster and Gnetum Ule. In spite of 
the difficulty of proving a case of parthenogenesis in living seed plants, 
LIGNIER* has given us a short paper with the rather startling title ‘‘ Bennettites 
Morieri probably reproduces by parthenogenesis.”’ One naturally looks for the 
evidence. Here it is. He found embryos, but no pollen grains or pollen tubes, 
and the tip of the nucellus was closed. Some of the sections were in series, at 
intervals of about 3mm. Presumably most of the sections were not in series. 
hen one remembers that pollen tubes have never been demonstrated in the 
Bennettitales and that very possibly the pollen grains may shed their sperms 
without the formation of a pollen tube, and that even in rather thick sections at 
intervals of 3 mm., more than nine-tenths of the material is missing, the evi- 
dence is not convincing. And yet, this “probable parthenogenesis” is given as 
a reason for the rapid disappearance of this group during the Cretaceous.— 
CHARLES J. CHAMBERLAIN. 
A classification of conifers ——Saxton™ has proposed a classification of 
conifers based upon the great extension of knowledge of the group developed 
during recent years. There is no question that the current classifications are 
archaic, and that a more natural classification of the group is demanded. SAX- 
TON analyzes the characters to be used in such a classification, and discusses 
the various attempts that have been made. He then describes, with definite 
i , Podocary , Pinaceae, Cupressaceae, 
and Taxaceae), Pinaceae having two subfamilies (Abietoideae and Sciadopitoi- 
deae) and Cupressaceae three (Cupressoideae, Callitroideae, and Sequoideae). 
A consideration of the phylogeny of Coniferales results in an interesting 
“family tree” that shows the relationships of the families and subfamilies. 
An interesting item of the phylogeny, at this time, is that the araucarians are 
represented as the first offshoot from the common stock (presumably abietin- 
ean) that arises from Cordaitales, which later gave rise to the podocarps, and 
then the other families.—J. M. C. 
characters. five families (A 
Ps \ 
Artificial parthenogenesis in Fucus.—Parthenogenesis in various members 
of the Phaeophyceae has been known for some time, and unfertilized eggs of 
Fucus have been caused to divide by treating them with solutions. OvERTON’S 
took exceptional care to obtain unfertilized eggs of Fucus vesiculosus, and each 
collection was divided into three lots, one of which was then fertilized, another 
was allowed to remain in normal sea water, while the third was treated wl 
3 LIGNIER O., Le Bennettites Morieri (Sap. et Mar.) Lignier se reprodusait 
probablement par parthénogénése. Bull. Soc. Bot. France IV. r1:125-127- 191! 
™ Saxton, W. T., The classification of conifers. New Phytol. 12:242-262. 1913- 
's QvERTON, J. B., Artificial parthenogenesis in Fucus. Science 37:841, 844- 1913: 
