R. T. LEWIS ON SOME PECULIARITIES OF A FLEA. 169 



follows : — " The Pygiclial appendages you enquire about have alto- 

 gether escaped my notice, but then I am not aware that I ever 

 examined the object with a higher power than lin. In the Eabbit 

 Flea I find something analogous situate on the last segment above 

 the Pygidium — but the slide shall be sent for your inspection. I 

 have not the smallest notion as to the probable uses of these appen- 

 dages. They are non-existent in any other Flea in my collection, 

 which numbers ten species." Mr. Tatem was kind enough subse- 

 quently to send me the slide of Rabbit Flea referred to, and the 

 sketch of the same now submitted is made upon exactly the same 

 scale as the larger one. The appended sketch of its Pygidium is, 

 however, on a considerably larger scale. The two small processes 

 which he mentions are easily seen, but neither in position, relation, 

 nor structure do they bear any resemblance to those noticed in the 

 giant specimen. A noticeable feature of the Pygidium of the large 

 Flea is the great number and comparatively small size of the areolae. 

 Those of the Rabbit, Cat, Mole and Hedgehog Fleas respectively, 

 count 28, 28, 28 and 24, as against 64 in this. 



The observation may not be of any particular value, but I should 

 like to make use of it to add further point to the recommendation so 

 often urged in this room, that our members should make drawings 

 of what they see. In no other way can things be so well impressed 

 upon the mind, nor is there any better training than this for habits 

 of careful observation ; the minute attention required in filling in 

 the details of a drawing will often reveal as literally as in the 

 present instance that, however simple may be the object, there is 

 very much more in it than at first appeared. 



