356 tHE CANAl)IAN NATURALIST. [Yol. 11. 



atelj high power. Nothing however, should be left untried, and 

 the very first comparison I made secured the desired result. The 

 pigment cells of a young Chironectes pictus proved identical with 

 those of our little embryos. 



It thus stands as a well authenticated fact that the common 

 pelagic Chironectes of the Atlantic (named Chironectes jnctus by 

 Cuvier), builds a nest for its eggs in which the progeny is wrap- 

 ped up with the materials of which the nest itself is composed ; 

 and as these materials are livina; Grulf weed, the fish-cradle, rock- 

 ing upon the deep ocean, is carried along as an undying arbor, 

 affording at the same time protection and afterward food for its 

 livins; freio-ht. 



This marvelous story acquires additional interest if we now take 

 into consideration what are the characteristic peculiarities of the 

 Chironectes. As its name indicates, it has fins like hands ; that 

 is to say, the pectoral fins are supported by a kind of prolonged^ 

 wrist like appendages, and the rays of the ventrals are not unlike 

 rude fingers. With these limbs these fishes have long been known 

 to attach themselves to sea-weed, and rather to walk than to swim 

 in their natural element. But now that we have become acquiant- 

 ed with their mode of reproduction, it may fairly be asked if the 

 most important use to which their peculiarly constructed fins are 

 put is not probably in building their nest. — SiUima7is Journal. 



pRor. Agassiz's Expedition. — It is probable that I may 

 have been anticipated, as regards part of the present communica- 

 tion. If not, I believe that many of your readers will be glad to 

 learn the objects with which Prof. Agassiz has started, with Count 

 Pourtales and a distinguished band of skilled observers, on a 

 scientific expedition in the United States' surveying ship IlassJevy 

 and to receive a brief account of what he has already done at St. 

 Thomas and Barbados, at which places he was obliged to touch, in 

 consequence of defects in the vessel or her machinery. 



The Expedition was detained some days at St. Thomas, and 

 the time of the Professor and his assistants was devoted chiefly to 

 the collection and preparation of fishes, with a view to the study 

 of the brain, and the breathing and digestive organs. Several 

 boxes full, preserved in alcohol, were at once shipped to the United 

 States, as the first-fruits of the Expedition. 



The party arrived at Barbados on December 26, and spent four 

 days there. The first two were devoted by the Professor to exa- 



