THE SO-CALLED JUMPING BEAN OF MEXICO. 311 



of mystification. The walls of the nut, being thinner than that of 

 the filbert, is parchment-like in texture, and quite permeable to 

 either sunlight or good artificial light. A good table-lamp effec- 

 tively arouses the maggot from a state of torpor and causes it to 

 make an effort to break through its prison walls. In any struggle 

 to be free, its body is made to assume the form of a ring by simply 

 hooking the rostrum and tail together, thereby placing itself in an 

 extreme condition of elastic tension. Then, on suddenly releasing 

 its hold, its horny head is projected forward with considerable 

 force against the drum-like side of the shell, presumably with the 

 view of breaking through the shell and making a way of escape. 

 The click thereby occasioned may be heard at some distance from 

 the spot on which the nut has been placed. The jump and the 

 action thus brought into play is at once recognised to be inter- 

 dependent upon the stimulus of light, heat, and muscle, which, 

 when conjoined, are plainly indicative of a rudimentary nervous 

 system, and which, on careful dissection, staining, and the aid of 

 the microscope, is easily made manifest. One's attention cannot 

 fail to be arrested by the wonderful display of nerve-fibres ramify- 

 ing through an almost transparent structure, and at stated intervals 

 along the sides of the soft body, and which terminate in a ganglia 

 and in a cavity analogous to that of the cranium and brain- 

 substance of the higher organisms. The larva is duly furnished, 

 as some few other species of insects are, with two or more spin-, 

 nerets. On cutting open a second nut a month later in the spring 

 of the year, a pupa was found enveloped in a fine-spun web ; had, 

 in fact, already passed into the pupa stage. On removing this 

 silken covering and the pupa, it was seen to be reduced in length, 

 measuring scarcely eight millimetres, it had assumed a dark-brown 

 metallic hue, and was only awaiting its further and final metamor- 

 phosis into that of the perfect insect — the weevil. 



It is well known the pupa does not feed, and that life is sus- 

 tained by the reserve of fat stored up by the maggot. On the 

 other hand, should the maggot fail in its attempts to break out of 

 the nut, it must certainly die in the early spring or summer months ; 

 but as the nut would drop from the tree in Mexico upon a wet 

 soil, a morass, the difficulty of breaking through the shell would 

 be considerably diminished. The jumping movements described 



