1917.] 261 



1'5 inm. long. On the 20th of the" same month larval exuviae were 

 extruded from these sacs. Dissection of the sacs showed that they 

 contained male nymphs. 



Apterous males commenced to emerge on the 28th. They are very 

 active, of a uniform dull reddish colour, with no definite division between 

 the thorax and abdomen ; the thorax is without hardened notal plates ; 

 the antennae are 10-jointed, all the joints short ; there are minute rudi- 

 ments of wings ; the genital sheath is short, slender, and acutely pointed ; 

 on each side of the penultimate segment is a prominent lateral tubercle ; 

 tliere are no caudal filaments. 



The females still appeared to be in the larval stage ; so it is difficult 

 to understand the function of this untimely brood of apterous males. 

 Signoret was probably referring to these apterous insects when he 

 describes the finding of "great qviantities of very agile male nymphs." 

 He goes on to remark that he had never seen " complete males." 



Female larvae were seen to be moulting and assuming the nymphal 

 stage early in May. 



On June 4th, adult females — -recognisable by a thin mealy deposit 

 on the marginal area — commenced to ajipear. In the meantime the 

 a])terous males had disa^jpeared. 



By June 9th, fully developed winged males w^ere emerging, and 

 copulation Avith the now adult females was observed. These winged 

 males differ from the apterous form in the stronger develojjment of the 

 thorax and notal plates, the squarer and more chitinized head, ample 

 wings, and long white caudal filaments. For some time before the 

 actual emergence of the insects, these caudal filaments could be seen 

 projecting from the hinder extremity of the puparia. 



After fecundation, rapid growth occurred, accompanied by the 

 development of the upturned secretionary fringe, and fully matured 

 females were observed by the middle of July. 



Young larvae were observed, on September 25th, wandering about 

 the stem of the tree before settling into their winter quarters in the 

 crevices of the bark. 



Mr. Fryer has reported the discovery of another small colony of 

 Gossyparia, on a " Golden Elm," in a nursery-garden at Knap Hill. 



Mriococcus devoniensis Green. 



Dr. Tmms has sent me typical examples of this species, taken at 

 Newehurch Common, Delamere, Chesliire. Although this is the third 



