. 39^ Scientific Intelligence . — Zoology. 
ascertained that what he had taken for a particular vegetable 
matter* was actually the oxalic acid. In the common Variola- 
ria, he found, in the 100 parts, 18 parts of lime, combined with 
S9.4 of oxalic acid ; nearly the same quantity of oxalate of lime 
was found in Urceolaria scruposa, Pertusaria communis, Isidium 
eorallinum, Patellaria tartarea, Baeomyces ericetorum, Squamaria 
lentigera, Placodium radiosum, Psora Candida. The oxalate of 
lime bears the same relation to the cryptogamia as carbonate of 
lime to corals, and phosphate of lime to the bony structure of the 
more perfect animals. The oxalate of lime diminishes gradual- 
ly in the family of lichens, in proportion as the species lose their 
granular crustaceous texture, and approach more and more to 
the membranous or cartilaginous, although these latter also con- 
tain a considerable quantity of this salt. From the vast abun- 
dance of these lichens, it is evident that they may afford a means of 
obtaining oxalic acid in great quantity, and at a cheap rate. The 
common Variolaria is found on the bark of almost every old de- 
cayed beech-tree (Fagus sylvatica ), in the form of large white 
subpulverulent rough crusts. It could be easily collected from 
such trees by scraping them carefully. 
zoology. 
18. Rectification of some popular errors regarding the Shark . 
— 44 Whatever may be said of the matter, the true Shark, Squa - 
lus C archarias, appears to us to inhabit almost every sea. It 
frequents the Atlantic Ocean, the Mediterranean, the shores of 
India, the Moluccas, the seas of New Holland, and those of the 
Archipelagos of the Pacific Ocean. In all these places, we 
have compared the species with one another, and we have every 
where found a perfect resemblance of forms. This animal is 
naturally slow in its motions, and we have never seen in it the 
vivacity of certain other fishes, even after it had been slightly 
wounded. This latter circumstance leads us to remark, either 
that its sensibility is much altered, or rather that the imperious 
feeling of hunger predominates over the pain ; for it is seen re- 
turning to bite and be caught by the hook which had torn it. 
Its voracity is extreme in certain cases, in others it does not exist, 
without our being able to account for the circumstances. We 
have seen sharks swim round the vessel for whole days, refuse 
