Catalogue Raisonni. ^73 



the kingdom of France, by Mr. Mathieu ; scientific notices by Mr. Arago ; 

 a continuation of his account of steam-engines, relating principally to their 

 accidents ; a sketch of Elie de lieaumont's view on the relative age of 

 the different jnountain chains of Europe ; and a notice of some of the re- 

 results of Mr. Pentland's researches in Peru. 



Zoological Researches and Illustrations. By J. V. Thompson, 

 Esq. F.L.S. &c.— No. III. Jan. 1830. Cork. King & Ridings. 

 This new number of Mr. Thompson's publication contains a memoir on the 

 cirripcdes or barnacles. In the language of a man mentally diseased, 

 the author announces the discovery of the larva of the Balanus pusillus. 

 Mr. Thompson, in a former number, advanced the opinion that the cirri- 

 pedes belong to the Crustacea ; and he considers that a confirmation of his 

 views is met with in the present discovery. 



Amongst the captives procured by a small muslin towing-net, was a 

 nondescript little translucent animal one-tenth of an inch long, of a some- 

 what elliptic form, but very slightly compressed laterally, and of a brownish 

 tint. When in a state of perfect repose it resembles a very minute mus- 

 sel and lies upon one of its sides at the bottom of the vessel of sea water 

 in which it is placed ; at this time aU the members of the animal are 

 withdrawn within the shell, which appears to be composed of two valves 

 united by a hinge along the upper part of the back and capable of opening 

 (rom one end to the other ^ong the front, to give occasional exit to the 

 limbs. The limbs are of two descriptions, viz. anteriorly a large and 

 very strong pair, provided with a cup-like sucker and hooks, serving sole- 

 ly to attach the animal to rocks, stones, &c. and posteriorly six pair of 

 natatory members. The tail which is usually bent up under the beUy is 

 extremely short, composed of two joints, and terminates in four setas, and 

 is employed to assist in progression and in changing the position fiom 

 a state of repose. The greatest peculiarity however in the structure of this 

 animals is the eyes, which although constantly shielded by the valves of 

 the shell, are pedunculated as in the Crab and Lobster, and placed an- 

 teriorly at the sides of the body." 



Having placed some specimens in a glass of sea water, after some days 

 he found that two of them had thrown off the exuvia, and were firmly ad- 

 hering to the bottom of the vessel, and changed into young barnacles ; 

 and afterwards another individual was seen in the act of throwing ofi" its 

 shell, and attaching itself as the others to the bottom of the glass. 



" In this stage the sutures between the valves of the shell and of the 

 operculum were visible, and the movements of the arms of the animal with- 

 in, although these last were not yet completely developed ; the eyes also 

 were still perceptible, although the principal part of the black colouring 

 matter appeared to have been thrown off with the exuvium. As the se- 

 cretion of calcareous matter goes on in the oompartments destined for the 

 valves of the shelly covering, the eyes gradually disappear, from the 

 increasing opacity thence produced, and the visual ray is extinguished fox 

 the remainder of the animal's life ; the arms at the same time acquire 

 their usual ciliated appearance." 



The number terminates with an addendum on a previous memoir oa 

 Nebalia. 



Bcschreebung des Koenigreichs Wurtemherg. — Description of 

 the Kingdom of Wurtemberg, published by order of Government, 

 by the Professor Memminger, INIember of the Royal Board of 

 Statistics, and of Topography. Cah. 1 — 6. 



This work may be considered as an authentic statistical and topographical 

 account of Wurtemberg. By the plan adopted each department will be 

 VOL. II. B 



