204 DAYS OUT OF DOORS. 



acute, although the eyes are exceedingly bright, and, when 

 coupled with certain movements of the head, suggest con- 

 siderable intelligence. It was foiind very difi&cult to test 

 their visual powers, although, once captured, these lizards 

 became extremely tame, patient, and obedient, and I could 

 only infer that the sense of sight was none of the best from 

 the fact that when held to a mosquito-frame in a window, 

 upon which house-flies were walking, they missed fully one 

 half of those at which they snapped ; and other lizards in 

 confinement, but where every possible freedom of move- 

 ment was practicable, often made many attempts to capt- 

 ure flies before success crowned their efforts. If, there- 

 fore, when at large, they depended principally upon winged 

 insects for subsistence, their lives would indeed be labori- 

 ous ones ; but insects of sluggish movements, ants, and 

 small spiders, are all freely partaken of. A friend who is 

 a very careful observer assures me that of the two insects, 

 house-flies and Croton-bugs, his lizards certainly preferred 

 the latter, but were not particularly expert in capturing 

 them. And now, assuming that the eye-sight of these 

 little reptiles is not highly developed, what of the curious 

 " pineal eye " which they possess ? Prof. Macloskie has 

 recently announced in " Science " that it " is so well devel- 

 oped . . . that it may probably seem to warn its owner of 

 the advent of daylight. It is a lenticular, glassy area of 

 the skin of the vertex (about a millimetre in sagittal di- 

 ameter), surrounded by a yellow border, and having a dark 

 spot in its center. The dark spot is opaque, caused by a 

 mass of pigment internal to the dermis, set on the extrem- 

 ity of a pineal outgrowth from the brain. The clear area 

 around it is caused by the dermis, which is transparent 

 and free from the pigment which covers it internally in 

 other parts. The eye is covered by an escutcheon- shaped 

 epidermal shield, more transparent in the center and 

 larger (three by three millimetres) than the normal spider- 



