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living crinoids has tended to verify the conclusions of palaeon- 

 tologists regarding this remarkable group ; and it may be 

 taken as certain that now, when beautiful and perfect examples 

 have fallen into the hands of such able naturalists, all doubtful 

 points in their history will be cleared up. 1 he second order 

 of the Echinodermata is composed mainly of the sand stars 

 and the brittle stars, species of which are abundant in our 

 bay. They are most active in their habits, and have a strange 

 faculty of dismembering themselves when captured, so that 

 there is some difficulty in preserving specimens entire. This 

 appears to be a provision for the safety of the animal. The 

 dismembered starfish has a power still more strange, by which 

 the lost limbs are replaced by new ones. Specimens are often 

 found in which new portions are in course of growth from 

 the broken rays. " Ophiocoma neglecta" a very small and 

 rare brittle star, is recorded by the late William Thompson as 

 found in Strangford Lough, and also near Bangor; it may 

 however, be found in abundance on the zostera banks at Holy- 

 wood. The third order consists of the so-called " cross-fish," 

 or five-fingers, sun stars, bird's foot star-fish, etc. It is repre- 

 sented in our waters by a number of species, of which 

 " U raster rubens," the common cross-fish, " Solaster papposa," 

 the sun star, are the most abundant forms. This group of Echi- 

 nodermata had its origin very early in geological time. The 

 lower Silurian rocks present us with star-fishes almost identical 

 in appearance with the " Uraster" of the present day. Through 

 all the vast changes that have taken place since the deposition 

 of the Cambro- Silurian rocks, this group has maintained its 

 place and is still flourishing. The fourth order contains the 

 numerous families of the " sea urchins," the species of which 

 present great variety of appearance as well as much elegance of 

 structure. This group is also a prolific one at the present day, 

 and has been an important one in most geological epochs. The 

 fossil "echini" are amongst the most highly prized objects of 

 thegeological collector. The sea cucumbers and seagirkins form 



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