362 Prof. A. M. Mayer's Experiments on tlie supposed 



yirovided with lunate eyes, between wliieh in front superiorly are 

 found two iiyrifonn capsules nearly touching each other, and 

 havinp: inij)lanted into them the very remarkable antenn.c. 



" The cai)suje, measuring about 0'21 niillim., is composed of 

 a horny substance, and is attached posteriorly by its ])edicle, 

 while anteriorly it rests u|)on a horny ring united with its fellow 

 by a transverse fenestrated band, and to which it is joined by a 

 thin elastic membrane. Externally it has a rounded form, but 

 internally it resembles a certain sort of lamp-shade with a con- 

 striction near its middle ; and between this inner cup and outer 

 globe there exists a space, except at the bottom or proximal end, 

 where both are united. 



•' The antennae are of nearly equal length in the male and the 

 female. 



" In the male the antenna is about 1*75 millim. in length, 

 and consists of fourteen joints, twelve short and nearly equal, 

 and two long and equal terminal ones, the latter measuring 

 (together) 0'70 millim. Each of the shorter joints has a fenes- 

 trated skeleton with an external investment, and terminates 

 simply posteriorly, but is encircled anteriorly with about forty 

 papillcB, upon which are implanted long and stiff hairs, the 

 proximal sets being about 0*79 millim. and the distal ones 

 070 millim. in length; and it is beset with minute bristles in 

 front of each whorl. 



" The two last joints have each a whorl of about twenty short 

 hairs near the base. 



" In the female the joints arc nearly equal, number but 

 thirteen, and have each a whorl of about a dozen small hairs 

 around the base. Here, as well as in the male, the parts of the 

 antenna? enjoy a limited motion upon each other, except the 

 basal joint, which, being fixed, moves with the capsule upon 

 which it is implanted. 



" The space between the inner and outer walls of the ca|i- 

 sule, which we term confidently the auditory capsule*, is filled 

 with a fluid of moderate consistency, opalescent, containing mi- 

 nute spherical corpuscles, and which probably bears the same 

 relation to the nerve as does the lymph in the scalar of the 

 cochlea of higher animals. The nerve itself of the antenna 

 proceeds from the first or cerebral ganglion, advances toward 

 the pedicle of the capsule in company with the large trachea, 

 which sends its ramifications throughout the entire apparatus ; 

 and penetrating the pedicle, its filaments divide into two por- 

 tions. The central threads continue forward into the antenna, 

 and arelobt there ; the peripheral ones, on the contrary, radiate 



* See figui-e, page 361. 



