384 BRITISH HYDRACHNIDiE. 



Texture : hard-skinned throughout, with a finely granulated 

 surface. The epimera is formed of a much thicker skin, and the 

 surface is much coarser than the other parts of the body. Eyes, 

 two, very distinct on the outer rim of the dorsal surface (Figs, i 

 and 5). 



Sexual differences : — The body portion, looked at from above 

 or from the dorsal surface, exhibits no difference in form or colour. 

 The male may be a little smaller, but both male and female vary 

 in size, so that this difference in size is of no intrinsic importance ; 

 but on the ventral surface a great difference can be seen (see Figs. 

 2, 3, 4, 6). Fig. 4 is the genital area of the male and Fig. 6 that 

 portion of the body of the female. The third pair of feet of the 

 male is also very different to the feet of the female (see Fig. 8). 



Distribution : — Not common. I have only seen eight speci- 

 mens. Dr. George, of Kirton-in-Lindsey, sent me three, Mr. 

 Scourfield two from Epping Forest, and I have taken three myself. 

 Although I am always collecting, yet during the last two years I 

 have not seen any. 



EXPLANATION OF PLATE XXI. 



Fig. 1. — Dorsal surface of 9 • 

 ,, 2. — Ventral surface of ?. 

 , , 3. — Ventral surface of 6 • 

 ,, 4. — Genital area of 6- 



,, 5. — Outline drawing, to show the arrangement of the dermal 

 glands and hairs. 



,, 6. — Genital area of ? . 

 ,, 7.— First leg of 6- 

 „ 8.— Third leg of <^ . 



The jaws of a true monkey have been found by Mr. Forsyth 

 Major in the ^pyornis beds of Madagascar. From their size 

 M. Gaudy infers that the animal was about as large as a man. 

 The molar teeth recall Mesopithems and Senmopithecus. In 

 general appearance the teeth resemble those of the Old World 

 monkeys, but their number corresponds with those of the New 

 World. For this new fossil Mr. P'orsyth Major proposes the 

 name Nesopithecus robertiis — Revue Scient. (4), VI., 1896. 



