188 Scientific Intelligence — Zoology. 



Seltzer water, are softened in twenty-four hours, as if in cliloroliy- 

 dric acid ; and the Seltzer water contains, afterwards, all the phos- 

 phate of lime contained in the ivory. This property, adds Dumas, 

 enables us to understand the introduction of phosphate of lime into 

 plants. These facts explain the disaggregation of bones, and the 

 dissemination of the phosphate of lime in the soil through the car- 

 bonic acid contained in rain waters; they shew how, in the animal 

 economy, bones may be redissolved by the venous blood charged with 

 carbonic acid; they indicate the part which the fluoride of calcium 

 acts in the teeth, in protecting the osseous portion from the carbonic 

 acid disengaged from the lungs, and dissolved also in the saliva, 

 which at the same time is alkaline, to neutralize the action of the acid. 

 Dumas suggests the use of carbonated waters for persons affected 

 with calculi of phosphate of lime. — U Institute No. 674. 



ZOOLOGY. 



9. Vampire Bats. — At sunset swarms of bats flutter through 

 field and forest in all directions, and greedily devour the insects which 

 in the twilight awaken to full activity. Some of these bats (Phyl- 

 lostoma hastatum, Geoff.) are remarkable for their expanse of wing, 

 which measures nearly two feet. Others are distinguished for ugli- 

 ness and for their offensive smell. These latter fly into the Indian 

 huts at night and greatly annoy the inhabitants, who cannot get rid 

 of them by fire or smoke, or any other means, until at the midnight 

 hour they retire of their own accord. Not less troublesome are the 

 leaf-nosed bats (Phyllostoma), which attack both man and beast. 

 This bat rubs up the skin of his victim, from which he sucks the 

 blood. The domestic animals suffer greatly from the nocturnal at- 

 tacks of these bats, and many are destroyed by the exhaustion con- 

 sequent on the repeated blood-sucking. The blood drawn by the 

 bat itself doefe not exceed a few ounces ; but if, when satisfied, it 

 drops down to the ground or flies away, the wound continues to bleed 

 for a long time, and in the morning the animal is often found in a 

 very weak condition, and covered with blood. One of my mules, on 

 which a leafed-nosed bat made a nightly attack, w^as only saved by 

 having his back rubbed with an ointment made of spirits of camphor, 

 soap, and petroleum. The blood-suckers have such an aversion to 

 the smell of this ointment, that on its application they ceased to ap- 

 proach the mule. These bats are very mischievous in the planta- 

 tions of the forests, where beasts of burthen and horned cattle are 

 exposed to their attacks. Whether they venture to assail man has 

 been a much disputed question. Several travellers declare that they 

 do not ; I may, however, mention a case which occurred within my 

 own knowledge. A bat (PA. erythromos^ Tsch.) fastened on the nose 

 of an Indian lying intoxicated in a plantation, and sucked so much 

 blood that it was unable to fly away. The slight wound was fol- 



