52 



rosoma be cut open and immersed in water, the bro^TO particles that 

 escape diffuse themselves throagh the fluid, and shine as numerous 

 scintillations, independent of the perfect structure. It is also wor- 

 thy of remark that general friction or contact is not essential to elicit 

 the perfect light of Pyrosoma, since touching one small portion of 

 the body is sufficient to produce a brilliant glow throughout the 

 \vhole. When first removed from its native element, the broader 

 extremity of this aggregate of moUuscs presented a wide and circular 

 orifice, forming nearly a continuous surface ivith the centrai tube 

 constituting the interior of the body ; but when kept in a vessel of 

 sea-water, or much handled, this oritice Tvas closed by the contraction 

 of a smooth, dense membrane at its margin, and which either obli- 

 terated the aperture, or left but a minute centrai orifice ; water at the 

 šame time being contained in the barrel or tube of the body. Ex- 

 ce])t in the action of this sphincter-like membrane, no motiA'e power 

 ■u-as perceptible in the Pyrosoma. 



" Fresh -vvater aj)pears to act as a powerful and permanent stimulus 

 on marine Noctiluca. 'JTliose Tvho have intervale of repose from their 

 phosphorescence immediately emit their light \vhen brought in con- 

 tact with fresh Avater, and this fact was very strikingly exhibited in 

 the Pyrosomata. When placed in a vessel of sea-water and permitted 

 toremain quiet, these molluscs afforded no light, andwhen touched, 

 gleamed forth only as long as the irritating cause remained, and then 

 gradually returned to their original statė. When, however, the šame 

 creatures were placed in a vessel of fresh water, they never ceased 

 glowing with their brightest refulgence until life was extinct, which 

 ■was not until after the lapse of several hours. When also the šame 

 molluscs were mutilated, or so near death as to refuse to emit light 

 upon irritation in sea-water, immersing them in fresh water produced 

 at least a temporarj^ revival of their brightest gleam ; indeed I have 

 always felt assured that the contact of fresh Avater in a darkened 

 room would ever elicit the luminous power of a marine creature, 

 ■were the latter of a luminous nature." 



At the request of the Chairman the following notes, relating 

 chiefly to the natūrai history of Ireland, were read by W. Thompson, 

 Esq.,'V.P.. Nat. Hist. Society of Belfast. 



Of the species so marked *, specimens were exhibited. 



Mammalia, 



* Vespcrlilio Nattereri, Kuhl. Reddish-grey Bat. I am induced 

 to exhibit a s pecimen of this bat, -vvhich I obtained in July 1 835 

 among the ruins of Harlech Castle, North Wales, it being hitherto 

 only kno\vn as British from individuals procured in the east and 

 south-east of England. 



* Mus Hibernicus. Irish Rat. On ąuestioning a person some years 

 ago respecting a black ratwhich he had seen in the north of Ireland, 

 my curiosity was excited by the statement that it had a whitebreast. 

 Li autumn lašt a similar description \vas given me of one that had 



