GEOMETERS. 



95 



The Black-veined, underside. 



The EGGS are laid on various grasses at the 

 end of June ; they are of a deep bright orange- 

 colour when deposited, but become almost 

 black before they are hatched, which event 

 usually takes place about the middle of July : 

 the young CATERPILLARS feed freely on knot 

 grass : they continue to grow slowly until they 

 are somewhat more than an inch in length, 

 when they retire for the winter, concealing 

 themselves among the steins of grasses, <fec., 

 which appeartobetheirfavouriteresort. They 

 now are long and slender, and rest on the knot- 

 grass, attached by the claspers only, the body j 

 being held semi-erect ; a slight bend occurs at 

 the ventral claspers, and another at the third j 

 pair of feet, the intervening segments forming j 

 an elliptic arch ; the head is porrected on a | 

 plane with the body, and the thi-ee pairs of 

 feet are directed forwards, but not crowded 

 together; when touched, shaken, or otherwise 

 irritated, the anterior segments are bent down- 

 wards and contorted until they almost form a 

 ring : head flat, porrect, exserted, of the same 

 width as the anterior segments : body very 

 slightly incrassated from the fourth to the 

 tenth or eleventh segment, transversely 

 wrinkled, and having a longitudinal lateral 

 skinfold, which, by increasing the width of the 

 caterpillar when stretched at full length, gives 

 it a slightly depressed appearance ; the anal 

 flap is deltoid, its apes terminating in a few 

 bristle-like hairs, which are directed back wards: 

 head and body putty-coloured, striped longi- 

 tudinally, the stripes varying only in intensity 

 of colour : a dark and very narrow medio-dorsal 

 stripe extends from the head to the tip of the 

 anal flap ; this is darker at the anal extremity, 

 and is not perfectly uniform in width, but ex- 

 pands and contracts here and there in its 

 course : this narrow stripe is intersected by a 

 median, thread-like, paler stripe : on each side 

 of the medio-dorsal stripe is a paler and 



broader stripe, containing a single series of 

 black dots, and being also longitudinally inter- 

 sected throughout by two thread-like rivulet 

 markings of a slightly darker hue ; each of 

 these pale stripes unites with the pale lateral 

 margin of the anal flap ; adjoining each pale 

 stripe is a darker stripe of similar width, and 

 this is longitudinally intersected by three paler 

 thread-like lines. Of these the middle one is 

 the most distinct : adjoining this is a paler 

 stripe, comprising the skinfold and spiracles ; 

 this commences behind the head, and termi- 

 nates in the anal claspers : below the pale 

 skinfold is a broader dark stripe, commencing 

 behind the head, and terminating in the 

 ventral claspers; this also is longitudinally, 

 but very indistinctly, intersected with paler 

 threads : ventral surface pale, longitudinally 

 intersected by three dark stripes, each of which 

 is double, or again intersected by a median pale 

 threadlike stripe ; these three ventral stripes 

 commence at the third pair of feet, and termi- 

 nate at the ventral claspers : legs and claspers 

 with the same shade of colour as the body. 

 After hybernation these caterpillars begin to 

 feed about the middle of April, and are full fed 

 by the middle of May, -when each spins a 

 delicate yellow shuttle-shaped cocoon, attached 

 longitudinally to a culm of grass. 



The MOTH appears on the wing in June, and 

 is very common in one or two localities in 

 Kent ; it is unknown elsewhere in England or 

 Scotland, but has been found by Mr. Birchall 

 in Ireland. (The scientific name is Scoria 

 dealbata.} 



221 . The Purple-barred Yellow (Lythria purpurarid) , 

 males. 



221. THE PURPLE-BARRED YELLOW. The 

 antenna3 of the male are strongly pectinated, 

 almost plumose, the pectinations long and 

 rather distant ; those of the female are only 

 pubescent : the fore wings are olive-yellow, 

 with the fringe and two or three transverse 

 bands, neither of which quite reaches the inner 



