NOTES. 
REPRODUCTION AND FERTILIZATION IN CYSTOPUS 
CAT^DIDXJS.- — In a paper read before Section D at the Edinburgh 
meeting of the British Association in 1892, on the structure of this 
Fungus, I gave a short account of the cytology and development of 
the asexual and sexual reproductive organs. This paper was incom- 
plete and in part somewhat incorrect; but since that time I have 
obtained fresh material and am now able to give a much fuller 
account, which will be published shortly in the Annals, and of which 
the following is a summary. The literature on this subject is not very 
extensive. Among those who have paid special attention to it are 
Fisch, Zalewski, Dangeard, and Chmielewsky. The results obtained 
by these observers are fully discussed in the complete paper. 
The Fungus is found as a parasite on the leaves, stem, and ovaries 
of various cruciferous plants, especially the common Shepherd's Purse 
(Cap sella Bursa- Pastor is\ on which it forms white shining patches, 
often of considerable size. The mycelium consists of non-septate 
hyphae, which ramify in all directions between the cells of the host- 
plant, produce small spherical hustoria, which penetrate the cells, and 
under certain conditions cause hypertrophy of the organs attacked. 
The mycelium is at first found only in the superficial layers of the 
plant, but at a later stage it penetrates into the deeper layers, and even 
into the pith. In the earlier stages of development this mycelium 
produces club-shaped branches just beneath the epidermis, from which 
the asexual organs (spores or sporangia) are delimited ; and at a later 
stage sexual organs (antheridia and oogonia) are produced on the 
ramifying mycelium, sometimes intercalary, sometimes terminal. The 
protoplasm of the hyphae is vacuolate, and consists of a loose network 
in which are to be found numerous small nuclei. In certain parts of 
