291 



MISCELLANEOUS. 



llie Development and Cliange in the Form of the Horn of the Gmi 

 (Connochetes gnu). Ey Dr. J. E. Gkay, E.R.S. 



Me. Edward Gerr.vrd, jun., has lately purchased the dead ])ody of 

 a half-gro-mi gnu which died shortly after it was imported. 



This animal is most interesting as showing the very great change 

 that takes place in the fonn and direction of the core of the horns 

 and the horns themselves during the growth of the animal. The 

 verj- young animal is figured hj- me in the ' Knowsley Menagerie,' 

 but I am not aware that the half-grown animal has ever been de- 

 scribed or figured. 



The horns in this state, instead of being bent down on the sides 

 of the front of the head, and flattened at the base, as in the adult, 

 are erect, cylindrical, conical, slightlj- curved, rather lyriform, some- 

 what like the horn of Damalis Innata, but less curved. The horns 

 are rather long, smooth, with a few indistinct rings near the base. 

 The cores of the horns are G inches long, conical, erect, like the 

 horns that cover them. The conical horn of this age forms the 

 conical elongated tip to the adult horn. 



At a certain age, the core and horn must be gradually bent back- 

 wards at the base, and at length they are produced and spread out 

 laterally until, as in the adult animal, they are decumbent on the 

 sides of the head, with a flattened base, recurved upward in the 

 middle, and straight and conical at the end. 



The horns on the skull of the half-grown, and especially of the 

 nearly adult animal are so unlike those of the adult, that, if they 

 had been received without the skin, it would be very excusable for 

 a naturalist to have regarded them as a distinct genus iiftermediate 

 between this genus and the lunated smooth-horned Damalis. 



The cores of the horns of the j'oung animal are somewhat like 

 those of the skull of the adult Xylghau, but not angulated at the 

 base, and more erect. "When the horns are more developed and re- 

 curved, as they must be in the intermediate age between the young 

 and the adult form, they must be very unlike those of any known 

 genus of hoofed animals. 



The skull of the gnu is peculiar for having the lateral Aving of the 

 basisphenoid extended into abroad pointed process in the back of the 

 orbit. This process is only very indistinctly seen in the figures of 

 the skull in the Catalogue oftheUngiilata Furcipcdain the Collection 

 of the British Museum, t. 15. f. 4, o^. 



On the Development of Cj-jiris. By C. Clacs. 



The earliest observations on the development of the Ostracoda are 

 due to M. Zenker. He found that at their Itirtli the Cytherides are 

 already provided with their two jtairs of antenna^ :in(l two pairs of 

 jaws, but that their abdomen is still but slightly developed and 

 bears only three little appendages in i)lace of the future limbs. In 

 18H5 M. Claus published some observations on the larvae of Ctqyris; 



