184 



Proetedings. 



[No. 9, NE"W SERIES, 



of them to cover one square inch, and that there are about 3,000 

 of them in one scale. 



No. 5. — Is a scale of a slightly different form from the same 

 wing, but magnified 820 diameters. 



No. 6. — Is a scale from a small species of Polyommatus usually 

 found in the same season and locality as the Thecla, scales of this 

 form are by no means common, and so far as I know, are confined 

 to the Polyommati. 



No. 7. — The Parasite of a Turkey, though of a very different 

 form belongs to the same order as No. 1. 



No. 9. — The house Flea, Pulex irritans, is well known all over 

 the world. Who has not read of trained fleas drawing Ivory car- 

 riages in golden harness : or of the enormous leaps they take, 

 equal to 200 times their own length, and which large figure I be- 

 lieve understates the fact. Of the trophi or parts of the mouth how. 

 ever less is known, as they cannot be seen without the Microscope. 

 *The mandibles are two elongated and flattened setse, with a central 

 rib, and with the f edges finely serrated ; these with the lingua 

 which is of equal length but more slender, are united in the mid- 

 dle of the mouth to form an instrument which from analogy with 

 the mouth of the suctorial Hemiptera is probably employed in 

 puncturing the flesh. At rest these organs are defended by the 

 labial palpi Avhich unitedly form a tubular hanstellum. The 

 maxillee are small, lamelliform, sub triangular appendages at the 

 sides of the mouth, and the maxillary palpi arise from their base 

 at the anterior emarginate extremity of the head." Such is the 

 mouth of the Flea. There are few I fancy who have not at some 

 time or other experienced how well it performs its work. 



No. 10. — Represents a part of the mouth of a Wasp, the mandi- 

 bles and head having been removed for convenience in mounting. 

 The broad blade like organs are the maxillae. The subjoined or- 

 gans are the maxillary palpi, that with only four joints is one of 

 the labial palpi, the other being out of sight, the central portion 



*Westwood. 



t Note— Westwood has overlooked the teeth on the surfaces of these 

 pieces, of which there is one, if not two, rows on each side of the central 

 rib, The teeth appear raised like those of a rasp. 



