﻿332 BE. L. MOTSEY ON PALJEOXYJRIS FBOM THE [Aug. I9IO, 



It is a narrow hollow stalk, composed of spirally arranged segments, 

 which expands somewhat suddenly into the body. 



The body is thin-walled and fusiform: its walls are formed of 

 the eight spirally arranged, alternately broad and narrow segments. 

 Its lower third is more expanded than the rest, and shows a marked 

 crumpling or deformity at this part (see PI. XXIV, fig. 1, A) 

 indicating that here was contained some body which has since 

 disappeared. In fact, in the Digby specimens at least, there is a 

 distinct cavity between the fossil and its counterpart in the lower 

 third of the body, which is filled with a white powdery substance. 



This substance has been in several instances subjected to 

 microscopical examination, with and without chemical solvents ; 

 but, so far, nothing has been found that throws any light on 

 its original nature. Chemically, this substance has been found to 

 consist of ferrous carbonate. 1 A careful search for phosphates, the 

 presence of which, it was thought, might point to the animal nature 

 of the fossil, has yielded only a negative result. If these fossils are 

 really egg-capsules, it is very unlikely that any relics of the embryo 

 would be found, as in all probability they would be the spent egg- 

 cases, drifted to their present position by currents ; just as rarely, 

 if ever, do we find the embryo skate still contained in the ' sailor's 

 purses' of our coasts. 



In the upper two-thirds the body tapers gradually to form a 

 distinct though broad neck, from which arises the beak (PI. XXIV, 

 figs. 3 & 4). The beak, a conspicuous feature in these organisms, 

 has not so far been adequately described — apparently, as the 

 existing published figures of Palceoxyris seem to show, because no 

 specimens have up till now been found exhibiting the beak in 

 a perfect state. It is nearly as long as the body, measuring 

 about 25 cm. in length, and is presumably of a somewhat more 

 resistant nature, as, in a specimen showing a crushed and contorted 

 body, the beak often appears uncrushed and complete (PI. XXIV, 

 fig. 3). It has a slight twist on itself, like that on the blade of a 

 ship's propeller. 



All the segments of the body enter into the formation of the 

 beak, but they run parallel to the long axis of the fossil, having 

 lost their spiral arrangement at the constriction of the neck. 

 After expanding almost to the width of the body, the beak 

 gradually tapers to a fine point. The beak was flattened, not 

 circular in transverse section as was the body, but whether it 

 contained a cavity or whether the corresponding segments were 

 approximated together, forming a more or less rigid, slightly 

 twisted, spear-shaped termination, it is impossible to say. There 

 is a definite arrangement of the segments forming the beak. First, 

 there is one narrow segment, gradually tapering to a point running 

 up the centre of the beak ; on either side of this are two broad 

 segments, which, slightly expanding at first, begin gradually to 



1 I am indebted for the suggestion of this experiment and the carrying out 

 of its details to Mr. R. D. Vernon, of Nottingham, to whom I would here 

 tender my sincere thanks. 



