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IL. Some Results of Recent Experiments in Hybridising 
Tephrosia bistortata and Tephrosia crepuscularia. 
By James WILLIAM Tutt, F.E.S. 
[Read November 17th, 1897. ] 
THE recent experiments made by Dr. Riding and Mr. 
Bacot in hybridising the two allied species, Tephrosia 
bistortata, Goeze (crepuscularia, auct.), and Tephrosia 
crepuscularia, Hb. (biwndularia, auct.), and the interest 
caused by the exhibition of the specimens, has led to the 
expression of a wish that some permanent record of the 
results exhibited by the various broods should exist. 
This is my only excuse for this paper. 
It is necessary to define the two species with which the 
experiments have been made, because it has been sug- 
gested that they really form but one species. The first, 
Tephrosia bistortata, is of an ochreous (often tending to 
ferruginous and fuscous) ground-colour ; it occurs in the 
British Islands in March and again in July, is widely 
distributed in Scotland and the southern counties of 
England, and is found in the greater part of the Palearctic 
and Nearctic regions. The ‘second brood of this species 
differs from the first in being, usually, smaller, of a dead 
white colour and almost entirely without the ochreous 
tint of the first brood. The second species, Tephrosia 
crepuscularia (biundularia), has a white ground-colour ; it 
occurs in the British Islands in May and June, that is, at 
a period intermediate between the two.broods of Tephrosia 
bistortata, is never double-brooded, is widely distributed 
in Ireland, and the midland and northern counties of 
England, overlaps T. listortata in the southern counties of 
England—in some cases occurring in the same woods, ¢.g., 
near Swansea, Leigh Woods (Bristol), the New Forest, 
Reading, &c.,—occurs in central Europe, but is not known 
to occur either in southern or northern Europe, nor be- 
yond European territory. 
So far, then, the specific separation of these undoubtedly 
allied species is insisted upon by many specialists. The 
points urged by them are: (1) The differences in the 
TRANS. ENT. SOC. LOND. 1898.—PARTI  (APRIL.) 2 
