444 
Notes. 
have as yet arrived at maturity. The resultant fern may depend, not 
only upon the variety from which a spermatozoid sprang, and upon 
that which bears the mature archegonium in which the spermatozoid 
is deposited, but a further change may be produced by the coales- 
cence of two prothalli. 
It is the general notion that only one archegonium out of a 
number on each prothallus is impregnated. It appears to me that 
several archegonia (if in a mature state at the same time) may be 
impregnated, and twin or triplet plants be produced. 
Transplanting the prothallus in the early stage before fronds are 
formed is a difficult operation, and the difficulty is increased if the 
endeavour is made to plant them singly ; if very thickly sown this is 
almost impossible. I always advocate planting at an early stage, and 
the modus operandi is as follows: — Small indents are made on the 
smooth surface of the soil after first watering it with a fine rose. The 
point of a penknife lifts the prothalli, and a gentle pressure with the 
finger pushes it into the indent. The moist soil damps the finger so 
that it is requisite to dry it between each operation in order that the 
fern shall not adhere to it. Looking back some years to the time 
when the Athyrium Filix-femina , var. Vidoriae was first discovered, I 
then used to raise spores in a modified Wardian case. This was 
kept under a shelf in a subdued light, and as the prothalli became 
mature, they were transplanted and placed in the full light of a green- 
house facing the north, and in this situation the fronds quickly appeared; 
not so those in the Wardian case in subdued light. For five years 
I kept transplanting crop after crop without ever sowing again, but in 
all that time no prothallus was ever known to form a frond whilst 
in the Wardian case in the subdued light. 
Of late years I have used for raising spores five-inch pots covered 
with flat glasses, and these have been kept plunged an inch deep in 
water; this has been done because less care is necessary during the 
earlier period of the germination of the spores. An excess of water 
does less harm than a defect, for under all circumstances the watering 
must be from below, as it is all but certain death to water the surface ; 
yet, if the soil is allowed to become dry the developing ferns are 
destroyed. 
In my experience I find no diminution in number of the progeny 
raised from various varieties of any species, but I differ from the 
opinion of those who say that hybrid species are equally prolific. It 
