of the Genus LithocoUetis. clxi 



in the middle of its abode, where it also collects its excrement into two 

 rows, and afterwards forms the cocoon of the pupa between them. 

 The larva is stout, 2 lines long; its middle rings, from the eaten pulp 

 of the leaf showing through, are sometimes greenish, sometimes dark- 

 er, otherwise the ground colour is pale yellow. The head and thorax 

 are greenish-yellow at the edges, and the ends of the jaws black. The 

 legs are sharp, rather darker than the skin, and the two of each pair 

 stand proportionally far apart. The prolegs appear as imperceptible 

 eminences ; of the anal prolegs I can see no trace. On the skin I ob- 

 serve very minute warts, on each of which is a small hair. The cha- 

 racteristics of the larva are very striking. Each ring has on the upper 

 side a short, but broad spot, which is more convex in front than be- 

 hind, and of a grayish yellow colour. These spots are all raised above 

 the surface. The spot on the first ring is divided lengthwise, that on 

 the second is the largest of all, the others gradually diminishing. Pre- 

 viously to its transformation, the larva forms at its place of repose a 

 fine elliptical cocoon, in which it spins up its excrement. The pupa 

 (at the beginning of July and middle of October) is almost 2 lines 

 long, goes gradually to a point behind, and has a very short caudal 

 spine ; the wing-cases are drawn out to a fine point, and reach dis- 

 tinctly beyond the three-fourths of the pupa. The palpi- and tongue- 

 cases are distinct, pointed, directed beneath, and projecting. The 

 colour is a very dark black-brown, the rings of the body rather paler. 



14. L. alniella, Tisch. Very common every year on alders, in the 

 pupa state. At the beginning of October, it is generally still in the 

 larva state. The larva is very pale, with transparent green streaks 

 and spots ; without further characters. The abode of the larva lies 

 generally in a corner, between the stout main rib of the leaf and one 

 of the side ribs ; it is moderately arched, and a small fold runs along 

 the epidermis in the middle, this is erected, not turned down or wrap- 

 ped over, as in most species ; the abode is usually therefore triangu- 

 lar ; rarely, it is placed between two parallel side ribs. The cocoon 

 of the pupa lies in the middle, it is dark yellow, of the consistence of 

 paper, very firm, and well fastened to the skin of the leaf: the pupa 

 is brown. Along with L. alniella, I found at Eckerberg L. Frolichi- 

 ella, which, being distinguished by its large mined abodes, is easily 

 detected from the outside. Both species frequent Alnus glutinosa as 

 well as A. incana. 



L. alniella appears in the room the earliest of all, from the middle 

 of December to the middle of January, after that only sparingly. The 



