1813.] Imperial Institute of France. 305 



well known. It is the family called echinodermes, which com- 

 prehends the star-fish, and other analogous genera. The Class 

 having proposed a prize for the perfecting of this branch of 

 comparative anatomy, it was gained by M. Tiedeman, Professor 

 in the University of Landshut. The memoir of this skilful 

 anatomist makes us accurately acquainted, for the first time* 

 with many particulars respecting the organization of these sin- 

 gular animals. A species of circulation is easily observed between 

 their organs of digestion and those of respiration, without, how- 

 ever, offering a complete double circle. Nor can the branches 

 be followed in the exterior organs, nor in those of motion. It 

 appears even, according to M. Tiedeman, that a quite different 

 vascular system is distributed to those numerous peduncles which 

 in these animals serve for instruments of locomotion. 



The organs of respiration differ much in different genera. In 

 the holothuria they represent hollow trees, whose branches fill 

 and empty themselves with water from without, and are inter- 

 laced with a vascular net. In the stars and urchins the water 

 penetrates immediately into the cavity of the body, and moistens 

 all the parts of it. 



This beautiful work, accompanied by plates exquisitely 

 finished by M. M'unz, Doctor of Medicine, appeared to the 

 Class to deserve the prize, by the number of new facts well au- 

 thenticated which it presents, and by the great progress which 

 it has made to the intimate knowledge of the echinodermes, 

 though it has not completely answered the question proposed 

 relative to their circulation. 



A family much more simple in its organization than the 

 echinodermes, but much more numerous in species, namely, the 

 coral-;, and other animals composed of a solid basis, has been 

 particularly sudied by M. Lamouroux, both with respect to the 

 .-pedes anil the methodical arrangement. This naturalist has 

 made a great collection of those whose basis is not stony, and 

 which present forms so agreeable, and often so singular; and 

 comparing with much care the form, the mutual position, of the 

 cells from which the polypi issue, and all the other visible 

 differences of these animals, he proposes to add 28 new genera. 

 is an important work for the perfecting of the system of 

 animals ; but it does not, from its nature, admit of an abridged 

 analysis. We are anxious for its speedy publication. 



M. Cuvier, proposing soon to begin printing the great book 

 on comparative anatomy with which he lias been occupied for so 

 many years, has presented to the Class a table of the divisions 

 SCCOrding to which the animal kingdom will be distributed in 

 that work. Naturalists have been long struck with the great 

 differences which separate animals without vertebrae from each 

 i, while animals with vertebra.' resemble euch other in so 



Vol. II. N° IV. U 



