40 
(Tulastoma) under the Lycoperdece. Much attention is given in this, as 
in others of Mr. Massee’s articles, to synonyms and references to litera¬ 
ture, and a complete Bibliography is appended, besides the very full 
references in the description of species. 
The plates are excellent, both from an artistic and a scientific point 
of view.—E. A. S. 
Wager, Harold W. T. Observations on the Structure of the Nuclei in 
Peronospora parasitica, and on their behaviour during the formation of 
the Oospore. Annals of Botany, November, 1889, pp. 127-146. One 
double plate. % 
The fact that even the general occurrence of nuclei in fungi has been 
and is disputed, and that only two observers have ever made any at¬ 
tempt to investigate the phenomena of karyokinesis, even where the 
presence of nuclei was unquestioned, renders this paper unusually in¬ 
teresting. 
The best results were obtained by imbedding the material in paraffine 
and cutting ribbon sections with a Cambridge microtome. By means of 
this process, the details of which are given, nuclei were found and their 
division watched in every portion of the fungus. 
In the hyphce. —The nuclei are most numerous where the liyphae ap¬ 
pear to be completely full of protoplasm, and in well stained sections 
the chromatin can be seen to arrange itself into threads, which are ar¬ 
ranged in the equatorial plane, and which finally separate into two 
groups, the divisions moving to the opposite poles of the nucleus. 
Neither the spindle nor the longitudinal splitting of the chromatic ele¬ 
ments were observed. 
In the oogonium and antheridium. —Large numbers of nuclei are pres¬ 
ent in both oogonia and antheridia; in the former they become arranged 
in a layer in the periplasm, and all, with those of the antheridium, pass 
simultaneously through the karyokinetic processes; two (or three?) of 
the nuclei of the oogonium then pass into the center, and a wail is 
formed, shutting out the periplasmic nuclei which rapidly divide into 
smaller ones. At the same time an antheridial tube is developed, into 
which some of the nuclei of the antheridium pass. Of these one probably 
passes into the oospore ; the remainder seem to pass into the periplasm 
of the oogonium, when the antheridial tube becomes disorganized. The 
ripe oospore contains several nuclei, and its endo- and exo-spore are 
formed from the periplasm and nuclei contained in it. 
In the gonidia. —The nuclei of the gouidia are larger than those of 
other portions of the fungus, and differ in structure. There are a large 
number in each spore, but neither their division nor their origin has 
been observed.—E. A. S. 
Ward, H. Marshall. Timber and Some of its Diseases. 8mo., 295 
pages. Macmillan & Co. 
The author, in this little volume, although treating the subject in a 
somewhat popular way, will especially interest the readers of this 
