Geological Society. 63 
this interesting form, is only to be reached by carefully 
tracing the different stages of its development, step by step, 
from the egg. In larvee of this stage the membranous interval 
between the bases of the last-formed (seventh pair) legs and 
the base of the setigerous penultimate sternum is found to 
be divided into two segments by a transverse groove ; the 
anterior of these segments is by far the longer, and the pos- 
terior is very short: to the extreme outer ends of the posterior 
margin of the latter are attached a pair of conical processes 
constricted at their base; they are the buds of the future 
eighth pair of functional legs, and they lie wedged between 
the setigerous processes and the caudal appendages, below 
(but in the same vertical line with) which they are attached. 
From the posterior margin of the longer and anterior of 
these two fresh segments, but rather nearer to the middle line, 
two similar, but much shorter, conical processes arise and lie 
appressed to the surface of the setigerous sternum; these are 
the buds of the future eighth pair of rudimentary legs. 
The addition of fresh somites therefore takes place in this 
animal by the intercalation of two at each moult between the 
antepenultimate and penultimate sterna, as in the Chilognatha, 
and as also in some of the Chilopoda, as far as some, at all 
events, of the somites are concerned, until the full number is 
attained. 
PROCEEDINGS OF LEARNED SOCIETIES, 
GEOLOGICAL SOCIETY. 
April 25, 1883.—J. W. Hulke, Esq., F.R.S., 
President, in the Chair. 
The following communication was read:— 
“ On the Skull of Megalosaurus.” By Prof. R. Owen, O.B., 
F.R.S., F.G.S. 
The specimens described in this communication were obtained 
by Edward Cleminshaw, Esq., from the freestone of the Inferior 
Oolite near Sherborne (Dorset) from some blocks which had been 
quarried for building-purposes. These were sent by him to the 
British Museum, where the remains have been developed. One 
block includes a great proportion of the right side of the facial part 
of the skull, the missing parts being the fore end of the premaxillary, 
the suborbital end of the maxillary, and the upper hinder pointed 
