170 



T. H. Withers — Shell-fragments 



sliell embedded closely together, and only one fragment shows the 

 outer surface. From their colour and appearance they evidently 

 belong to more than one form of shell, but it is impossible to discover 

 much from the inner surface of mere shell-fragments. 



The most conspicuous fragment is the irregularly triangular shell- 

 fragment marked II in Fig. 1, and this was Seeley's "tergum". It 

 is really the anterior ear of a right valve of a Pecten with a part of 

 the remaining shell, and shows the inner surface. The sub- 

 cylindrical shell-fragment regarded by Seeley as continuous with it 

 and as the "beak" of the "tergum", does not appear to me to 

 belong to it. Above the " tergum " is a four-sided shell-fragment (I) 

 called by Seeley the " scutum ", but this is an indeterminable shell- 

 fragment quite unlike the inner surface of the scutum of a Cirripede. 



Fig. 



Zoocapsa dolichorhampMa Seeley. 

 Pollicipes alatus Tate. (After Tate.) 

 Scalpelluin solidulum Steenstrup sp. 



6. 



(After Darwin.) 

 (After Marsson.) 

 (After Karakasch.) 

 (After Woods.) 



Aucellijia gryphcsoides Sowerby sp. 

 (Figures drawn by Miss G. M. Woodward.) 



Projecting from under the "tergum" is anotker fragment (III) 

 with slightly elevated wavy ribs, crossed at right angles by growth- 

 lines. This is the only fragment showing the outer surface, and tlie 

 ornament of it agrees very closely with that of the Pelecypod Lima 

 gigantea, Sowerby. It represents Seeley's "upper latus". On the 

 opposite side of the "tergum", is another fragment (IV) regarded 

 by Seeley as one of the compartments, but though Molluscan it is 

 impossible to say to what shell it belongs. Professor Seeley stated, 

 " Altogether the plates preserved would incline one to suspect that 

 there were no more." It is apparently to be understood from this 



