NOTES AND MEMORANDA. 411 



derm which take place in the head being the foundations of the 

 internal cephalic skeleton. The latter consists, firstly, of a hollow 

 rod bridging over the occipital foramen, and, secondly, of the chiti- 

 nous bands which stretch from the foramen to the angle of the clypeus. 

 These bands are hollow, and in the region of the brain are dilated into 

 a vesicle which communicates with the exterior by a tolerably wide 

 aperture. 



7. There is a true lower lip which must be looked upon as the 

 serial homologue of the labrura. 



8. The thin inner egg-membrane, lying beneath the chorion, is 

 quite evident even in the youngest stages, before the formation of the 

 blastoderm. 



9. The cells of amniotic epithelium often send out processes 

 which meet and fuse with the cells of the ejiiblast, and so form 

 strongish bands connecting the epiblast with the amnion. 



10. The tergum of the embryo is formed by a gradual narrowing 

 of the root of the amnion, as a result of which process the cells of 

 the tergal epiderm long resemble the flat amniotic cells. 



11. Lal"ge cells become separated off from the epiderm, and remain 

 unchanged to the end of the embryonic development, even existing in 

 the young larvas as lateral cell-aggregations (Zellencomplexe). 



12. In the epidermis itself very large nucleated cells are found 

 among the ordinary small cells : probably these have some relation to 

 the development of hairs. 



Venomous Caterpillars.— Mr. E. D. Jones, C.E., Corr. Memb. of 

 the Literary and Philosophical Society of Liverpool, relates, in the 

 Proceedings of the Society,* an experiment he made with a cater- 

 pillar in Brazil, on 28th February, 1878. The species is not given, 

 but it is described (with a plate) as 1^ inch long, very thick in pro- 

 portion to its length, and the whole body covered with long red- 

 brown hairs, which grow in tufts arising from the centre of each 

 segment, and at the base of the long hairs are bunches of venomous 

 spines which are quite concealed by the hairs. The body is very soft 

 and fleshy, and of a paler colour than the hairs. The head is very 

 small, and is when eating quite covered with a fleshy mantle formed 

 by the first segments of the body. 



Feeling certain it was an exceedingly venomous caterpillar, he 

 determined to sting himself with it. 



At 11 A.M. he applied the back of the caterpillar to the back of 

 his left hand, with suflicient pressure to feel the pricking of the 

 spines. In ten minutes he had violent pain in the hand, and the 

 place of contact had swelled up into a white lump surrounded by 

 a dark-red inflamed patch. A few minutes later, violent pain set in 

 under the armpit. At 11 .30 a red rash apjjeared on the inside of the 

 elbow, and this gradually extended up to the shoulder, along the 

 biceps, and down the arm to the place of injection on the hand. 

 The rash was slight, excepting just at the elbow. Soon after 12 there 

 was a sensible weakness of the hand and arm, either an eft'ect of the 

 extreme pain or a distinct eficct of the jioisou. At 12.15 the rash 

 * xxxii. (1878) p. cii. 



