Notes . 
5i i 
insects. In many species a conidial form of reproduction, not pro- 
duced on the surface of the compact stroma as in Claviceps , but 
borne on an erect, branched structure, appears first, being followed 
by the higher form of reproduction, the globose or club-shaped head 
bearing the perithecia being supported on a stem varying in length 
in the different species from one-sixth of an inch to six inches in 
length, the entire fungus being often eight inches high, as in Cor- 
dyceps Rohertsii , Hook., parasitic on a large caterpillar in New 
Zealand. As a rule the larva is attacked by the fungus, the conidial 
fructification being produced on the active pupa, which often succumbs 
to the parasite, the higher fructification appearing after death. In 
other cases both forms of fruit mature on the still living caterpillar, 
or in other species one or both forms of fruit appear on the living 
imago state, as in some species of Lepidoptera. The great advantage 
to the fungus, from the point of view of spore-dissemination, of 
having the mature fruit raised on a long stalk and carried about, 
especially by a winged insect, is obvious. 
The number of species included in the above-named genera are as 
follows : Oomyces , 1 ; Epichloe , 3 ; Claviceps , 3 ; Cordyceps , 47, and 
the genus is cosmopolitan. 
G. MASSEE, Kew. 
ON THE OCCURRENCE OP DIASTASE IN POLLEN 1 .— 
The germination of the pollen-grain and the formation of the pollen- 
tube involve questions similar to those which arise in connection with 
the germination of the seed. In both cases we have to deal with the 
utilisation of certain reserve materials which in the case of the pollen- 
grain are stored within it. As the pollen-tube has to attain a certain 
length before it can avail itself of any external nutriment which it may 
find in the tissue of the style, it is evident that the material which it 
uses in the early period of its growth must be the result of the trans- 
formation of the starch, sugar, &c., which are part of the contents of 
the grain. 
In these processes ferment* action plays a definite part. Some 
years ago, Van Tieghem found that he could demonstrate in the 
pollen-grain the presence of invertase which converts cane-sugar into 
glucose. In the present paper an account is given of certain experi- 
1 Abstract of paper read at the meeting of the British Association, August, 1891. 
N n a 
