346 ANNUAL OE SCIENTIFIC DISCOVERT. 



placed on the outside of their bodies have got for them their name of 

 naked-gilled. 



In the fourth tank are also contained some species of barnacles and 

 sea acorns (Cirripedia^) which with their hard molluscous-like shells 

 were once included under the mollusca, but are now known to have 

 an internal structure which allies them with the articulated tribes of 

 animals. In this tank are some small species of sea-fish ; including the 

 blenny, the fifteen-spined stickleback (first cousin to the well-known 

 fresh water sticklebacks, which have mostly only three spines), the 

 wrasse and the father-lasher (Cottus bubalis). The annelides are rep- 

 resented in several of the tanks by species of aphrodite and the beau- 

 tiful sabellse. Many of the leaf-like and vegetable-looking objects at 

 the bottom of the tanks are popularly called sea-weeds, and demand a 

 microscope to make out clearly their animal nature. 



One of the most interesting features in this novel exhibition is the 

 restless change of position among the several creatures. The visitor 

 may occupy the whole day in passing inside and outside the building 

 from tank to lank, and yet every time see something new. The tanks, 

 visible on both sides, afford 390 square feet of view, and contain seven 

 tons of sea water. Of the marine fish, of which the Blennies and 

 Cotti are almost always at the bottom, it may be said that their habits 

 are being now, for the first time, investigated with success-; and their 

 activity and rapacity present effects so curious that the most casual 

 observer cannot help being struck with them. This exhibition of liv- 

 ing fish and invertebrates^ besides exciting much curiosity, will be of 

 most impressive usefulness to the student, to whom they have been 

 only known hitherto by books and dried remains. 



BAKE SHELL. 



At a recent sale of shells in London, being a collection formed by 

 the late Earl Mountnorris, the interest of conchologists was much ex- 

 cited by a species of great rarity and much value, called Cyprcca prin- 

 ceps, or " The Brindled Cowry of the Persian Gulf." Only one other 

 specimen, formerly belonging to Mr. Broderip,and now in the British 

 Museum, is known, aud from their great beauty and freshness, their 

 very peculiar typical character, and the number of years, nearly 

 half a century, that have elapsed since their discovery, it provoked a 

 strong competition. The first offer for it was twenty guineas. After 

 several biddings it was knocked down at 40/. 



ON THE WEIGHT OF MAN. 



At the British Association, Mr. Milner said that season seemed to 

 have an influence on the weight of man. He had weighed the pris- 

 oners in Hull gaol for five years, and had found that they regularly 

 increased in weight from April to November, and decreased in weight 

 from November to March. The diet was the same all the year round, 

 as was also the temperature. 



