1882.1 13 



will be formed, and just below it are one or two small bristles. I have 

 observed this in A. divinatoria (reared by myself), succinica, and olea- 

 ginn, and also in Hyperetes tessellatus. So long as the young have 

 only two-jointed tarsi, the antennae have also less joints. Thus, in 

 A. divinatoria the latter have only 12 instead of the 15 of the imago ; 

 in Hijperetes the proportions are 13 to 23. But, although the third 

 (middle) joint of the tarsi is produced by a division of the apical, it 

 is just the contrary with the antennae. In these the two thick basal 

 joints, and the apical joint, are not divided ; but in some species all 

 the intermediate joints are so. Hyperetes is in the latter case, all the 

 10 intermediate joints being divided in the imago, as I can show from 

 preparations. It is a remarkable fact that the mysterious Hyperetes 

 shows, in its earlier stages, precisely the normal number (13) of joints 

 for the PsocidcB. I am not prepared to give an opinion as to this 

 genus. Other genera, such as Ccecilius, commonly considered to have 

 only two-jointed tarsi, possess a small aborted third joint, just as oc- 

 curs in many Coleoptera. 



Cambridge, Mass. : 



1st April, 1882. 



FOOD-PLANTS AND TIMES OF APPEAEANCE OF THE SPECIES OF 

 PSYLLID^ FOUND IN GREAT BEITAIN, TOGETHEE WITH 

 OTHERS WHICH MAY BE EXPECTED TO OCCUR HEEE. 



BT JOHN SCOTT. 



The publication of the synonymic list (vol. xviii, p. 253) corrected, 

 as far as I possibly could, to that time, naturally led me to think of 

 giving, in a collected and comprehensive form, as complete information 

 as possible of the food-plant of each of the species, together with the 

 time when the latter may be looked for ; and, although they may be 

 found a little earlier or later than the time here' indicated, yet this 

 shows when they were actually taken. But very little is still known 

 of the earlier stages of many of these insects, of others nothing what- 

 ever, and the solution of this problem in any one of these cases I 

 consider to be of much greater importance than the capture of the per- 

 fect insect itself. I have already, in vol. xvii (p. 132), explained my 

 mode of rearing them, and how easy this is to be done, so that I need not 

 repeat it. Eor the purpose of keeping this table as simple as possible, 

 I have only used the old and well-known generic names ; the recent 

 sub-divisions being given in the list above referred to. 



