This insect (new to Britain) being analogous to several groups 

 that are widely distributed through the extensive family to 

 which it belongs, it became necessary to pay particular atten- 

 tion to its structure ; and I was much gratified to find that 

 Hiibner had given a figure of its larva in the same plate with 

 those of Geometra sexalisata and lobulata, thereby confirming 

 the opinion that 1 had formed when I assigned it to the si- 

 tuation which it now holds. The 3 larvae, as might be ex- 

 pected, are very similar; and I regret that I did not meet with 

 it in time to introduce it into the plate : it is bright green be- 

 neath, duller green above, with a narrow yellow line down 

 each side. (Vide Hiibner'' s Supp. Gcometrce 11. JEquivocce G. 

 a. b. fig. 2. a. b.) 



This pretty genus now contains 6 British species, which 

 must form 2 divisions. 



* Inferior wings of males with large lobes, poste- 

 rior tibiae with 2 pair of spurs. 



1. L. sexalisata Hiib., Haw. 



2. hexapterata Fab., Haw., Don. v. 6. pi. 1 92. 



** Inferior wings with small lobes, posterior tibiae 

 with 1 pair of spurs. 



3. lob u lata Hiib. — dentistrigata Haw. 



4. costaestrifjata Haw. 



5. polycomata Hiib. 



6. viretata Hiib. — trinotata Don. v. 14.^/. 499.^/] 1. 1. 

 I would wish here to call the attention of the student to the 



structure of the legs of our species (one of each pair being 

 figured, and in which I believe all those of the 2nd division 

 agree), the posterior tibiae being deficient of a character, which 

 I have never seen wanting in any other group of this family, 

 all other Phalcenida having another pair of spurs below the 

 middle. It is also worthy of remark, that Geometra multi- 

 strigaria Haw., and G. dilutata Hiib. and Haw., have the re- 

 markable oval spot beneath at the base of the wings, and that 

 in habit it somewhat resembles, Phalcena rujata Fab., and 

 Phalcena brumata Linn. ; and it is probable that L. polyco- 

 mata will assist in bringing together these species, which are 

 now so unnaturally scattered through the family. 



Two females of our insect were taken in a lane near Dart- 

 ford Heath, Kent, upon Black Thorn, the beginning of April 

 1824; and Mr. B. Standish took two males upon the wing 

 the 10th April this year, in the same place. 



Primus spinosa (Sloe Tree or Black Thorn) is figured vdth 

 the insect. 



