March-Arpil 1S90.] 



PSYCHE. 



323 



appear all during the last of Juh, 

 August and September, the young and 

 old, in various stages of growth, appear- 

 ing together. Whether the broods 

 appear later than September I cannot at 

 present tell, as my observations on the 

 species v^^ere abruptly terminated by the 

 yellow-fever epidemic. 



The newly hatched larva is shown in 

 figure b. It is of a pale greenish white 

 color and less than 2 mm. in length, and 



insect assuming more and more the 

 appearance of the imago ; the cephalic 

 prolongation disappears with the third 

 molt, when the frontal carinae are more 

 or less distinctlv visible, as well as the 

 three carinae on the thorax, and distinct 

 wing pads appear. 



There are two distinct forms of 

 imagos — a perfect winged and a brachyp- 

 terous form — which are briefly described 

 below, being, it is believed, together 



in some of its characters quite dissimilar 

 to the adult : The head has a remark- 

 able cephalic prolongation, shaped as 

 in the figure ; the thorax exhibits dorsally 

 six quadrilateral plates ; the abdomen is 

 composed of 7 segments, the basal one 

 being the longest ; the middle and an- 

 terior tarsi are only i -jointed, while the 

 posterior tarsi are 2-jointed, the posterior 

 tibiae being without the large movable 

 spur, so characteristic of the adult. 



From this stage to the adult there are 

 five distinct molts, after each molt the 



with the figure, sufficient to distinguish 

 the species. 



Delphax ma id is ?i. sp. 

 $ Length 2 mm. ; wing expanse 6|- 

 mm. Pale greenish-yellow, in death 

 pale brownish yellow ; apex of i st and 

 the apical half of 3nd antennal joints, 

 lower part of frons, spots on pleurae, 

 most of the abdomen, except the ist 

 ventral segment and the lateral edges of 

 the dorsal segments, smoky black. 



Legs pale, the femora more or less em- 

 browned ; apex of posterior tibiae with 



