* 
“378 Biographical Notice of Edward Forbes. 
/£gean Sea and on the adjacent coast of Asia Minor, which alone 
would have immortalized his name. At the same time he neg- 
‘lected .no occasion of studying the geology and botany of the 
regions which he visited; but the dredge and its results will ever 
remain’ the chief glory of this expedition. The results of these 
researches were made known to the public in the ‘ Report on the 
Mollusca and Radiata of the Aégean Sea, and on their distribution, 
considered as bearing on Geology,’ made to the British Associa- 
tion at their meeting at Cork in 1843. From this report it ap- 
pears that the data on which it was founded were entirely derived 
e Aégean, when but a few days passed by without being devo- 
ted to natural history observations. The calculations were based 
on more than 100 fully-recorded dredging operations in various 
depths from 1 to 130 fathoms, and in many localities from the 
shores of the Morea to those of Asia Minor. And with that mod- 
esty which ever characterized Edward Forbes in all his works, 
he adds, that the merit of the results is mainly due to Captain 
Graves. The chief objects of the report, as stated by the author, 
were, ‘‘to give an account of the distribution of the several tribes 
of mollusca and radiata in the Eastern Mediterranean, exhibiting 
their range in depth and the circumstances under which they are 
found ; to inquire into the laws which appear to regulate their 
distribution, and to show the bearings of the investigation on the 
science of geology.” 
I shall not attempt to give an analysis of this valuable report ; 
I shall content myself with reminding you of some of the more 
important conclusions, as bearing on geological investigations, 
which are embodied in it. The most important fact which has 
resulted from them respecting the development and distribution of 
animal and vegetable life in the depths of the ocean is, that of 
the almost uniform occurrence of particular species in particular 
zones of depth below the surface. This distribution of marine 
animal life is determined by three primary, modified by several 
secondary, influences. The primary are climate, sea composition, 
; of the many secondary influences, the most import- 
ant is the character of the sea bottom. According as rock, mud, 
sand, weedy or gravelly ground, prevails, so will the number of 
the several genera and species vary. The outline and geological 
nature of the coast is also an important feature in modifying the 
marine fauna. Other secondary influences are tides and currents, 
the influx of fresh water, &c. 
_ We have then a full description of eight well-marked regions 
of depth in the Eastern Mediterranean, each characterized by its 
peculiar fauna, and when there are plants by its flora. ‘These re- 
gions are distinguished from each other by the association of the 
species they severally include. Certain species in each are found 
r 
