198 PROCEEDINGS OF THE 



Mr Peter Cameron exhibited various specimens of Tenth re- 

 dinidae, new to the British Fauna, taken by Mr Joseph Chappell 

 in the Manchester district. (1) A new species of Dolerus, dis- 

 tinguished from all the other black and red species by having the 

 abdomen entirely red, otherwise nearly approaching D. lateritkis, 

 Klug; (2) Blennocampa micans, Klugj (3) Lyda fulvipenniSy 

 Zaddach, a species described in 1863, when only two specimens 

 were known in the Berlin Museum, Mr Chappell's example being 

 thus the third. Mr Cameron also showed Athalia annulata, Fab., 

 taken in England by the Rev. T. A. Marshall. This species 

 was erroneously inserted in our lists, but as we have now this 

 authentic specimen, it may again be included in the British fauna. 



PAPERS READ. 



I. — On Saxicava rugosa, a Bivalve Mollusc; showing an unusual mode 

 of repair. By Mr David Robertson, F.L.S., F.Gr.S. 



It is a common occurrence to see shells which have been repaired 

 by the animal after accidental injuries of various kinds. These 

 repairs, it is well known, are accomplished by a calcareous 

 secretion applied to the points of injury, whether a fracture, a 

 bruise, or displacement of parts, which are often mended even 

 when the fractured edges do not come into proper contact ; and 

 in such cases, the shell frequently assumes a more or less contorted 

 appearance. This calcareous secretion is also used by the animal 

 to cover any irritating substance which happens to get inside the 

 valves of the shell ; and when this occurs with any of the pearl- 

 bearing molluscs, the foreign objects get covered, layer after layer, 

 with nacreous or pearly matter, and in this way pearls are formed. 

 This property is said to be taken advantage of by the Chinese, 

 who place little figures of their gods within tlie valves of such 

 shells, where they allow them to remain a sufficient time to be 

 coated over with a pearly covering. 



Here is an injury to the shell of a mollusc, Saxicava rugosa, — an 

 injury of a different kind, — not accidental, but purposely inflicted 

 by a carnivorous univalve mollusc, which has the power of drilling 

 through the covering of hard shell to reach the animal -wdthin, and 

 with much skill, if we may so call it, in selecting the most 

 vulnerable point of attack. It will be seen by the perforations of 

 these boring molluscs, in the numerous examples before us, that 

 they have been done by no random aim, but so directed as to 



