26 MORPHOLOGY OF SPECIES 



Fig. 3. — Genital area of female. 

 ,, 4. — Genital area of male. 

 ,, 5. — Genital area of nymph. 



Teutonia primaria (Koenike). 

 ,, 6. — Ventral surface. 

 ,, 7- — Genital area of male. 

 ,, 8. — Genital area of female. 

 ,, 9. — Palpus of female. 



©baeivations on tbe flDorpbolog^ of Specice 

 of tbe (5enu6 TTlIey. 



By Harold Wager, F.L.S. Plates IV. and V. 



THERE are two species of C//ex to be found in England, 

 U. EuropcEUs and U. nanus, and a variety of the latter 

 known as Gallii, both common in most parts of the 

 country, and familiar plants to all who are acquainted with our 

 heaths and commons. Although apparently so distinct in the 

 structure and general appearance of its vegetative organs, we may 

 compare the genus Ulex with the genus Cytisus, which it resem- 

 bles in many respects in regard to its morphological characters. 

 In Ulex we have what may be regarded as an extreme modifica- 

 tion of vegetative structure in response to the environment, \vhich 

 in Cytisiis is not so far advanced, and in the following pages we 

 shall endeavour to describe this modification, how it has probably 

 been brought about, and under what conditions. 



The commonest species, U. Europceus, is distributed very 

 widely, being found in the w-estern parts of the old world from 

 north-west Africa to Shetland Islands, and ascending to a height 

 of 2,ioo feet in Wales. It is a shrubby bush, about three to five 

 feet high, with a very compact habit when grown in the open, but 

 a rather straggling habit when grown in the shade. This compact 

 habit is due, in large part, to the regular mode of branching which 

 it possesses and to the development of short spiny branches in the 

 axils of the leaves. The plant likes deep and somewhat loamy 



