STRUCTURE AND CLASSIFICATION OF THE FOSSIL CRUSTACEA. 179 



is closely analogous to the action of nitrite of amji. Inhaled in quantities 

 of not less than a grain, it induces the same sensation of fulness of the head, 

 rapid action of the heart, and some suffusion of the skin. Animals subjected 

 to it in the proportion of fifteen minims diffused as vapour through a cubic 

 foot of air, die almost instantaneously from sudden failure of the heart, but 

 even up to the moment of death they retain their consciousness and sensi- 

 bility. The nitrite, consequently, is in no sense to be regarded as an 

 anaesthetic. 



Precisely as the nitrite of amyl, nitrite of ethyl, when it kills, leaves the 

 lungs entirely collapsed and so perfectly white that one could assume they 

 had been carefully washed free of blood. This effect is due perhaps to the 

 rapid contraction of the pulmonary capillaries. The blood is changed in 

 colour, the arterial blood being rendered very dark, and the venous of a deep 

 chocolate tint* ; the muscles are also all left blanched, as if the death had 

 occurred from loss of blood. 



It will be remembered that, in describing the action of nitrite of amyl, I ex- 

 ,plained that in cold-blooded animals the substance suspended their animation, 

 and that frogs that had been rendered powerless by it, and to common obser- 

 vation inanimate, would sometimes spontaneously recover even so long as nine 

 days after the administration. This same phenomenon I have observed with 

 nitrite of ethyl, together with another even more singular. It is this. If a 

 young animal, say a kitten, be subjected so suddenly to the nitrite as to fall 

 senseless and to appearance dead in or within the minute, it will remain in the 

 same state for six or even ten minutes, yielding no evidence of life : it will 

 not breathe, and the most delicate auscultation will fail to detect motion 

 of the heart. But after a. period vaiying from six to ten minutes it wUl 

 spontaneously recommence to breathe, and with every movement of expiration 

 a breath sufficient to dull a mii-ror wlU pass from the nostril. As the breath- 

 ing recommences, the heart also begins its work, making a series of distinct 

 intermittent strokes. This condition, looking like an actual return of life, 

 will last so long as half an hour, and will then cease gradually, the animal 

 lapsing again into a state of actual inertia or death. 



In concluding this Report I would place the facts I have collected, in 

 respect to the ethyl series, as follows : — 



1. Oxide of ethyl, or pure rectified ether as it is commonly called, is the 

 best of all known agents for the production of general anaesthesia by 

 inhalation. 



2. The peculiar difference of action between the oxide of ethyl and the 

 nitrite of ethyl is due to the introduction of a new element, nitrogen, into 

 the latter compound. This difference of composition makes the nitrite approach, 

 in action, bodies of the alkaloidal class, strychnine and its analogues. 



Second Report on the Structure and Clafisification of the Fossil 

 Crustacea. By Henry Woodward, F.G.S. 



I HAVE now to submit a Second Report upon the Fossil Crustacea, which 

 have for some years past occupied my attention. Since the last Report 

 made to the British Association in Birmingham in 1865, I have described and 

 figured a new liassic Crustacean from the Lower Lias of Charmouth — the 



* The coagulation of blood is not modified. 



n2 



