Insects. Ib21 



or white. This shows that Hartig's assertion is incorrect, namely that 

 the Nemati are contained " im einfachen dichten aber nicht dicken 

 Cocon " (' Die Familien der Blatt. und Holzwespen,' 180). 



The larvae which I had taken at the Hague appeared in the month 

 of October of the same year ; on the other hand, those which I had 

 taken at Leyden remained over the winter, and about the end of April 

 I found in one of the cocoons a small shining green pupa of a glassy 

 appearance. Antennte, palpi and legs pale green ; eyes black ; the 

 ocelli were very perceptible through the outer skin. The perfect 

 insect emerged from the pupa state in May. This difFei'ence in time 

 can probably only be accounted for by a difference in temperature. 



The perfect insects (fig. 4) are 4j lines long, the males somewhat 

 less. The whole body is of a blue-black colour, very shining, the head 

 and thorax finely punctulate. The antennte are three lines long and 

 black ; the joints sharply divided ; the palpi are brownish red at the base. 

 The nieta-thoracic spots are dirty white ; in the female the abdominal 

 segments have very narrow gray margins. The legs are red, with 

 black coxae ; the hind legs have the tarsi and the posterior half of the 

 tibiae black. In some individuals the coxae are one half yellowish 

 red, others have the tibiae black, with the base red. The wings are 

 transparent, yellowish at their insertion ; the nervures partly red and 

 partly black, with a large bluish black stigma; the nervure between 

 the first and second submarginal cells is almost always merely indi- 

 cated. The perfect insects seldom appear, at least I have rarely 

 observed them, and Dr. Hartig has seen only one specimen, which 

 was minus the hinder tarsi. 



I have examined the parts of the month of this species of Nematus. 

 The labrum (fig. 5) is broad and but little protuberant, but has a serai- 

 circular appendage ; the mandibles (fig. 6) are broad and short, curved, 

 with a sharp-pointed apex and a small tooth in the middle ; the maxillae 

 (fig. 7) are corneous, with a membraneous discoidal apex, and a sharp- 

 pointed membraneous appendage on the inside ; externally are the five- 

 jointed maxillary palpi, the third joint being the longest and thickest ; 

 the labium (fig. 8) is quadrate, but rounded at the apex, with three 

 processes, of which the middle one is very narrow ; on each side is a 

 palpus consisting of four joints, of which the second is the thickest, 

 the terminal joint is abruptly rounded oflT. 



The abdomen of the male (fig. 9), has an oval plate on the seventh 

 segment. The edges of the corneous plates of the dorsum of the abdo- 

 men extend some distance over the ventral plates, so that they are 

 always visible on the under side. 



