A NEW BRITISH COCCtD. 261 



Larval and second stages not observed. 



Eggs pink or pinkish-yellow, dusted with a mealy powder. 

 Length 0-30 to 0-35 mm. 



Habitat: — On Erica cincrea: Budleigh-Salterton, S. Devon; 

 August, September. 



My attention was first drawn to the insect by its habit of distorting 

 the young shoots of the plant upon which it fixes itself. In many 

 cases the terminal part of the shoot is twisted up in a rosette-shaped 

 knot, enclosing one or more of the insects. Other shoots are bent at 

 right angles at the point of irritation. This distortion occurs only 

 when the insect has attached itself to the young growing parts of the 

 plant ; the older stems are not affected in the same way. 



In August, when the insects were first noticed, the female sacs 

 were already packed with ova, the female being much shrivelled, and 

 occupying the anterior extremity of the sac. The male sacs had 

 apparently been vacated for some time. No other stages of the insect 

 were observed ; but the white sacs of the adult insect were abundant, 

 and widely distributed on this one species of Erica. Not a single 

 example occurred on either the common heath or the " ling " {Gal- 

 luna vulr/aris). 



I at first supposed the species to be Eriococcus ericae, Sign. ; 

 but a microscopical examination proved it to be both specifically 

 and generically distinct (according to Signoret's classification). The 

 7-jointed antennae separate it from typical Eriocnccm, but allow 

 of its inclusion in PJuwcoccus, though Mr. Maskell considers that 

 that genus should be reserved for species that remain naked in the 

 final stage. Signoret, in defining the genus, says : — " It closely 

 resembles the preceding species of the genera Eriococcus and Acantho- 

 cocciis, but without the sac ; perhaps it possesses one later. But in 

 any case, it must form a distinct genus on account of the T-jointed 

 antennfe." The structural character being the same, the presence or 

 otherwise of an ovisac would scarcely be of generic importance. The 

 same differences are allowed, without question, in the genera Dacty- 

 lopius and Pseudococciis. Personally I am also of the opinion that the 

 number of antennal joints — other characters being similar — is insuflfi- 

 cient for the separation of the genera, and that Eriococcus and Rhizo- 

 coccus might be combined under one name. 



It will be noted that the present species has six hairs only on the 

 anal ring — an unusual number — all the other members of the genus 

 being apparently possessed of eight. 



Description of Plate III. — Fig. 1. — Rhizococcus devoniensis, Green, adult J 

 dorsal view. Fig. 2. — Rhizococcus devoniensis. Green, adult $ ventral view. Fig. 

 3. —Rhizococcus devoniensis, Green, antenna of adult $ . Fig. ^.^Rhizococcus 

 devoniensis, leg. 



The Antennas of Lepidoptera. Their structure, functions and 



evolution. 



(Concluded from j)- 228). 

 By J. W. TUTT, F.E.S. 



The senses which are supposed to have their peripheral organs in 

 the antennae are those of touch, taste, smell and hearing. (1) Touch. — 

 It is supposed that the several types of sense-hairs already described 

 are especially adapted for the reception of tactile impressions. The 



