201 SELECTED NOTES FROM 



by Mr. Cox, Mr. Lowne also expresses the same view — viz., that 

 adhesion is effected by means of a viscid fluid poured out from 

 the hairs, and states * that the foot-prints left upon glass by the 

 house-fly consists of rows of dots corresponding to the hairs. 



He describes, moreover, the sac which secretes this viscid 

 fluid, which, he says, fills the whole of the last four tarsal joints. 

 He has also described this sac in Dytiscus, but I cannot at the 

 moment refer to it. I certainly cannot see hooks in the slide sent 

 by Mr. Locock, but bulbous tipped hairs. A. Hammond. 



Boring Sponges.— I'liese were taken from an oyster-shell. The 

 oyster has many foes to contend with, and hundreds of them are 

 destroyed by the boring sponges, which riddle the shells with 

 holes and then live on their victims. This was certainly the case 

 with the oyster from which these objects were taken, for the shell 

 was bored through and through, and when opened contained 

 nothing but mud, the poor oyster having met with an untimely 

 end. M. A. Henty. 



Oyster shells perforated with holes drilled by these Clione 

 are often to be seen at the fishmonger's. When examined 

 fresh, with a good pocket-lens, these shells will be seen to be 

 coated and lined with a yellowish substance, which forms part of 

 the Cliona or Boring sponge. How it excavates these holes and 

 cavities is a mystery; but it seems to have the power of dissolving 

 away the lime for the purpose of living on the animal matter con- 

 tained in the shell. The holes are generally of two sizes — the 

 larger for the emission of oscular tubes ; the smaller, which are 

 much more numerous, for the poriferous tubes. On splitting the 

 shell open, both are found to communicate with irregularly sunken 

 canals, occupied by the yellowish coloured body of the sponge. 



To obtain a good collection of the spicules, boil this yellow- 

 looking substance in dilute nitric acid, and abundance of spicules 

 will be found. No doubt the animal uses these in its borings. If 

 the oyster fresh from the sea be placed in a vessel of cool sea- 

 water, delicate mobile tubes will be seen protruding from the 

 various apertures. Those from the larger holes end m a single 

 oscular opening; those from the smaller expand at the end into a 



* Lowne's Anatomy of the Blow- Fly ^ p. 21. 



