32 



further study of this subject, and especially as to one or two 

 doubtful points of some interest. 



The specimen which yielded the most satisfactory results, was 

 one of the largest I have ever seen, being 5^ feet long, and 8 

 inches in circumference. It was a female, and contained 16 

 more or less matured eggs. The fangs were very prominent, 

 beincr |. of an inch long from their apex to the point of their 

 insertion in the sockets ; the mucous fold below contained, on 

 each side, seven supplementary fangs of a graduated size, and 

 the development of which in their capsules I described in the 

 previous paper. On the left side, there were two fangs at- 

 tached, of equal size — the old one external, and the new one 

 internal — this coexistence being due to the persistence of the 

 old fang, until the relations of the new one should be fully esta- 

 blished. The canal of this old fang was more or less obstructed, 

 and it was evident that it had not been used for some time. The 

 canal of the new fang, on the other hand, was pervious, but con- 

 tained no poison. The duct of the poison gland did not appear 

 to connect with the base of either fang, but lay between them, 

 apparently in a state of transition from the base of the old fang 

 to that of the new. 



On the right side, there was only one fang fixedly attached, 

 the next succeeding fang lying in its future socket, but its anchy- 

 losis not yet having taken place. Here, the duct of the gland 

 communicated with the base of the fang, its fibres embracing, 

 fan-like, the portion including the commencement of the canal of 

 the fang, but not, as is stated in books, entering this canal. In 

 this way the current of the poison would be direct and continuous 

 from the duct to the external end of the fang where it is dis- 

 charged into the wound. 



It would appear, then, from this examination, that the succes- 

 sion of fangs takes place in the following manner : — The new fang 

 appears behind, pushing upwards as it grows ; posteriorly and 

 somewhat internally to the socket of the old fang, it acquires its 

 socket and becomes attached therein ; as this attachment is be- 

 coming complete, it pushes still further forwards, at the same 

 time crowding the old fang outwards, and finally takes its 

 place more or less exactly. By this lateral pressure, the socket 



