DisTEiBUTioN m DErxn 



153 



rare Panopcea Norvegica are swallowed, and ejected again with, 

 eroded surfaces. The haddock swallows shells still more indis- 

 criminately, and Mr. M'xindrew has found great numbers of 

 rare Pectens in them, but generally spoiled. The cat-fish and 

 skate break up the strongest shell-fish with theu' teeth — account- 

 ing for the many angular fragments met with in the dredge, 

 and in recent deposits. 



The following are examples of shells obtained from great 

 depths : — 



Nonvay. (M'Andrew.) 

 Living shells. 



Fathoms. 



Ceritliium metula 20—150 



Margarita cinerea 10 — 130 



Dentalium entale 200 



Limea sarsii 120 



Leda pj-gmeea 200 



Yoldia limatula 120 



Thetis koreni 40—100 



Ciyptodon flexuosus 200 



Off the Cape. (Belcher.) 



Buccinum? clathratum 136 



Volutilithes abyssicola 132 



Pectimculus Belcheri 120 



uEgean, (Forbes.) 



Living. Dead. 



Terebratula vitrea 100 250 



Argiope decoUata 100 110 



Crania ringens 9) 150 



AL(jcan. (Forbes.) 



Living. 



Murex vaginatus 



Fusus muricatus 80—95 



Na^sa intermedia 



Ceritliium lima 3 — 80 



Cliemnitzia fasciata ... 



Eulima distorta 



Scalaria helleuica 



Eissoa reticulata 55 



Troehus exasperatus ... 10 — 105 



Scissurella plicata 



Acmea unicolor GO — 105 



Dent all jm quinquangulare 



Bulla utriculus 



Spondylus Gussonii ... 105 



Pecten Hosk3-nsii 



Ai'ca imbricata 00 — 230 



Neffira cuspidata 12 — 185 



Thetis anatinoides 



Kellia abyssicola 70 — 180 



SjTidosmya profundissima 



Dead. 



150 



150 



45—185 



140 



110—150 



69—140 



110 



185 



165 



70—150 



150 



150—230 



40—140 



185—200 



40—150 



200 



80—185 



Preserving molluscous animals for examination. 



When shell-fish are killed by sudden immersion in hot water 

 or strong spirit, great and unequal contraction is caused, d's- 

 torting the muscular parts and rupturing the membranes. 



Experiments have yet to be made for the discovery of means 

 whereby these and other marine animals may be paralysed and 

 killed, without altering the ordinary condition of their organs.* 



Glycerine is the best medium for preserving such objects as 

 the univalve shell-fish, intended for the examination of their 



* Tlic brittle-stars {Ophiocomd) are killed by sudden immersion in fresh-water; and 

 the AdinicE may be stupified by adding fresh-water drop by di-op until they lose the 

 power of retracting their tentacles. But the bivalves (such as Pholas) may be kept in 

 Btale water till their valves fall off with incipient decomposition, and yet the muscular 

 siphons retain their irritability, and contract slowly and completely, when placed in 

 spirit. 



h3 



