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ON BRITISH MARINE ZOOLOGY. 
@ ig 192 5 95 | oo] Fe) 2s | sehsl a8 [Ξ8 
Φ x ne ῷ 9 24 Ba. 8 
British genera. a3 44 Ξ a os 2 28 Be a aga Ξ = : ES g 
ge 23 28 | 22°) 28 | 3g | se 355. es 8 ΞΞὃ 
a | a ees |. a ee als —_ [== | .-............. 
Test. Morxusca. 
GASTEROPODA. 
Purpura ....0....sc0.0000, 1 1 | (1) are πο tra) 1 1 1 1 
Murex .......... HUM 3 2 2 4 1 2 1 1 1 8 
GSMS) FAs νον ἃ lie weal 9 0 2 Ρ 3 2 6 4 6 3 
Buccinum ............... 4 1 1 a 1 1 2 2 2 0 
ΟΥ̓ΘΕΒΒΙ cs rept. wis ctas ἐμ. 8 2 3 Ν᾽ τῷ 9 2 1 ἢ 
Trophon............ Sees ie 0 1 Dara (Oe 2 3 3 3 1 
Mangelia ...... afin Ms 15 0 9 see [| 2k. el 11 15. | 34 
Marginella ...... ἐὰν ἢ 1 3 1 ce I 1 1 0 5 
0) SE BPR SO eae RIN 0 0 RZ SELEY 1 0 4 
POCA ταν seca ον τινα 1 1 1 de 1 1 1 1 7 
Tornatella ............... 1 1 1 sez : 1 1 1 2 3 
linea γδϑὴλ lim οι 0 7 ἢ 3 8 4 18 | 13 
|: Coe ai a 6 0 2 ὃς 1 4 3 4 3 
Pleurobranchus.........) 2 2 Deni 0, ἘΣ 1198 * 0 1 6 
Aplysia ....... τῆς ἠδ 1 0 1 F eet * 1 0 1 6 
Conovulus ............... 2 2 0 τ Ἀ 1 ὃ 3 
EcHINODERMATA. ; 
Comatula ....... ashi ate 0 1 5 1 2 vie 2 1 
Ophiura ............ rt etl eb Or} = 2 Saf 2 2 0 1 3 
Ophiocoma.......... fe cl EY 2 5 1 5 6 0 10 11 
Euryale ........... ἰὼν sey [LOR 0 0 van 0 * 0 3 1 
Uraster .......... SEE. out 4 | 8 4 εὐ Zee ἃ 1 3 3 
MORI PUAN, coisas cs cue neces cy 2 1 1 = 1 1 0 2 1 
ΠΗ irr 2 0 2 kit 1 2 0 3 ὃ 
Palmipes............. ἔξ} 0 0 uy 1 1 0 0 1 
Asterina ........... AS 1 1 0 as * * 0 0 3 
Goniaster ....... ΠΣ 2 0 0 1 1 1 0 4 1 
JASLETIAS 0 :,. ᾿ς ἀρνί 1 0 1 Ap = 1 1 0 4 4 
Luidia.......... Ἐπ τος sea 1 0 1 Ἢ ie, 1 1 0 1 1 
Echinus .................. 7 2 3 Et 1 2 4 1 6 7 
Cidaris ............ Bayar 1 0 0 ἐς ἫΝ 0 * 0 1 1 
Echinocyamus ......... 1 0 1 ὡς ᾽ 1 1 1 1 1 
Brissus ....... Loy ont 1 0 1 3 0 1 0 2 2 
Amphidetus ............ 2 1 2 1 1 ? 2 2 
Spatangus ...............| 1 0 ΤΡ ΤΟΣ 1 1 ? 1 1 
Causes which seem to determine or to have determined the peculiarities of the 
horizontal distribution of Species on the western coast of G'reat Britain. 
These seem to be mainly,—first, the influence and distribution of existing 
oceanic currents; and secondly, the geological changes which the region has 
undergone since the tertiary epoch, and during the last term of that epoch. 
The first is the climatal influence, acting by its regulation of the temperature 
of the sea; the second, a geological influence, the action of which, so far as 
the present epoch is concerned whilst under review, has passed away. 
_ Along the southern coast of England, the upper portion of the Coralline 
zone (18-30 fathoms) has a wide extension from the shore towards the eastern 
extremity of the English channel, occupying its whole breadth and gradually 
narrowing along the coasts of Devon and Cornwall, where the deeper por- 
tion of the same region approaches the land more nearly than elsewhere 
on the western English coast*. To the extension and connection of lands 
* The naturalist, besides consulting the usual hydrographical charts, cannot do better 
than study the interesting Map of the English Channel by Mr. Austen, published in the 
Geological Journal. 
