1883. ] Zoblogy. 93 
to that employed in the English expeditions ; with dredges of the 
usual pattern, to which the commander, M. Richards, added two 
bouteilles a eau,” ingen- 
ious bottles invented by M. Richards for taking samples’ of water 
at any determined depth. 
The scientific work was thus apportioned: A. Milne Edwards, 
crustacea ; M. de Follin, editor of “ Les Fonds du Mer,” rhizopoda ; 
Professor Le Vaillant, fishes; Professor E. Perrier, echinoderms ; 
Professor Marion ccelenterates and worms; and M. Fischer, mol- 
lusks and worms. 
The depths of the Mediterranean, often 2600 metres below the 
surface, are covered entirely with a homogeneous, sticky mud, 
without so much asa pebble, but in certain places this mud is 
strewn over with an enormous quantity of the delicate shells of 
such pelagic mollusks as Hyalea, Carinaria, etc. This homoge- 
neous mud, the result of the immense amount of sediment con- 
tinually carried into this inland sea by the numerous rivers that 
flow into it, does not appear to offer favorable conditions for the 
development of animal life, since what most struck the attention of 
all the naturalists was the rarity of the organisms inhabiting the 
depths, when compared with the astonishing riches of the surround- 
ing coasts. Throughout these depths, not only is there a monotony 
of muddy surface, but no currents change and agitate the water, 
and the temperature, beyond a depth of 200 metres, appears to be 
always 13° centigrade. The discovery in the Mediterranean of 
many forms believed to be peculiar to the Atlantic, and in the latter 
of those believed to be confined to the Mediterranean, has proved 
that the fauna of that sea had its origin in the ocean by way of the 
Straits of Gibraltar. | 
In this connection we cannot do better than translate the words 
of A. Milne Edwards, at the conclusion of his address to the 
Academy of Science, Paris : 
“Tt results from our researches, that the Mediterranean ought 
not to be considered a distinct zodlogical province; the more its 
Species are studied, the more it becomes evident that those forms 
believed to be limited to it can be found elsewhere. 
_ “ The observations made by the Travailleur lend a new force to 
this opinion. We believe that the Mediterranean is peopled by 
animals from the ocean. These finding in this recently opened 
‘sin conditions favorable to their existence, have established them- 
selves there definitely; in many cases they have reproduced and 
developed themselves more actively than in their first habitat, and, 
especially near the coasts, the fauna shows a richness that the other 
uropean coasts rarely show. Some animals, placed in new bio- 
logical conditions, are slightly modified in form or in other exte- 
nior characters, which explains the slight differences which may be 
observ between certain oceanic forms and the corresponding 
