436 Bibliographical Notice. 



small individuals are sometimes swallowed by larger ones, when 

 they will continue to live in the cavity of the body of their de- 

 vourers for weeks, without any apparent mutual inconvenience. 

 The animals are able to adhere with any part of the body, 

 probably by means of the urticating threads, which indeed ap- 

 pear, even in the tentacular filaments of the Medusae, to be more 

 serviceable as adhesive organs than by their venom. They not 

 unfrequently climb up on the wall of the vessel, and then usu- 

 ally adhere by the mouth. Before they distend themselves in 

 order to rest comfortably, their form is very changeable, accord- 

 ing as one or another part of the body is more strongly con- 

 tracted, the tentacles retracted or extended, and so forth. All 

 their movements are very slow : when left quiet, they remain 

 for days lying at the bottom of the vessel, or hanging from the 

 same part of its wall, without any other movements than con- 

 tractions of the annular muscles, which from time to time 

 proceed from the anterior to the posterior part, in slowly ad- 

 vancing undulations. 



EXPLANATION OF PLATE VII. Fig. 4. 

 Philomedusa Vogtii, in the distended state, magnified three times. 



BIBLIOGRAPHICAL NOTICE. 



Handbook to the Geology of Weymouth and the Isle of Portland; 

 with Notes on the Natural History of the Coast and Neighbour- 

 hood. By Robert Damon. 12mo. E. Stanford, London, 1860. 



A Supplement to the Handbook to the Geology of Weymouth and 

 the Isle of Portland. By Robert Damon. 8vo. E. Stan- 

 ford, London, 1860. 



" When George the Third was King," and Weymouth the royal 

 wateringrplace, few indeed of its visitors cared for amusing them- 

 selves by natural-history pursuits more definite than the finding or 

 buying a few odd fossils, or collecting some shells and sea-weeds as 

 curiosities. But modes are much altered with the times ; and a large 

 proportion of the visitors and residents at Weymouth, as at nearly 

 all other places of resort for invalids and tourists, have some know- 

 ledge of the common things around them, or at least know that 

 real pleasure is to be obtained by the proper exercise of that almost 

 instinctive faculty we all possess of examining for ourselves every 

 animal, plant, and mineral we can find, and getting a systematic 

 knowledge of them. Most guide-books, therefore, now-a-days have 

 some sort of geological appendix for the benefit of those whose eyes 

 are open to the many points of interest, in the structure and physical 

 history of a district, which are invisible to the uninitiated ; but here 

 we have a Geological Handbook — and a very good one too — for a 

 pleasant locality, rich with a variety of interesting geological phaeno- 



