1S65.] Zoology and Animal Physiology. 333 



lateral laminaB of the caudal fin, and the false feet. The organs remain 

 latent, the latter until the second month, the former until the third. 

 At each moult some organs become complete, others acquire more and 

 more their normal form, whilst others make their first appearance to 

 arrive subsequently at their final perfection. It is probable, therefore, 

 that the same species of Phyllosoma in different moults, has been de- 

 scribed under various names, and M. Gerbe feels assured that he will 

 soon be able to prove that if the Phyllosomata of authors present 

 more perfect characters than the larva of the Palinurus, as described, 

 it is because they have undergone several metamorphoses, and, conse- 

 quently, represent subjects in a more advanced state of development. 

 Phyllosoma, therefore, bears the same relation to Palinurus that the 

 Zoea does to the Crab. 



M. Guyon has communicated to the French Academy some 

 researches upon the poison of Scorpions, from which he deduces that 

 it is identical in its character with that of serpents, both affecting 

 animals in a similar manner. Both poisons produce more violent 

 effects upon small animals than on large ones, and on warm-blooded 

 than upon cold-blooded ones. The scorpion's sting is followed by 

 immediate violent pain, and general itching, tumefaction, and 

 extravasation of blood into the subcutaneous cellular tissue. Trem- 

 blings, vomiting, and great prostration succeed. Eespiration is 

 accelerated, and coma ensues in fatal cases, with dilatation of the 

 pupil. Tetanic spasms of the extremities (more frequent in birds 

 than in mammals), and remarkable disturbance of the genito-urinary 

 organs, also occur in many cases. 



Dr. V. Hensen has shown that the Crustacea possess a delicate 

 sense of hearing, and describes the organs by which this sense is 

 developed. His researches have extended to twenty-eight species of 

 Crustacea. In the higher forms a delicate nervous filament enters a 

 chitinous hair, which is connected to the rest of the chitinous skeleton 

 in such a manner as to allow of vibrations under the influence of 

 sonorous undulations. The extremity of the hair often penetrates 

 between the otolites, or even into the interior of one. The otolites are 

 thrown off at the periodical moult, together with the chitinous tunic, 

 and are replaced by others, and the minute lapilli are introduced by 

 the animals themselves into the auditory sac. In Crustacea with a 

 closed sac, however, they present a peculiar structure, but still they 

 shed the auditory apparatus, which is reproduced anew. The auditory 

 hairs are of three kinds: — 1. Hairs with otolites; 2. Free hairs of 

 the auditory sacs ; and, 3, Auditory hairs of the outer surface of the 

 body. The first are generally curved, and recall the setas in the ordi- 

 tory organ of fishes. The Brachyura (crabs, &c.) have no otolites, but 

 their auditory sacs are nevertheless furnished with hairs, of which he 

 counted 300 immersed in the fluid of the auditory sac of the common 

 shore-crab. Inasmuch, therefore, as auditory hairs may be thrown 

 into vibration without the mediation of otolites, M. Hensen thinks it 

 is probable that they may be equally capable of fulfilling their func- 

 tions if they were placed on the surface of the body. These conside- 



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