TRANSACTIONS OF THE SECTIONS. 133 



Recent researches on the structure of the Infusoria show that some members of 

 that group, for example Vorticella, present a more or less obvious differentiation of 

 their primitively homogeneous tissue into imperfect layers. A mouth, also, is con- 

 stantly present. In these characters the higher Protozoa pre-indicate, as it were, 

 certain structural features which are seldom absent among the members of other 

 sub-kingdoms. So also do the more advanced Ccelenterata, and especially the 

 Ctenophora, foreshadow, in a manner, the anatomical peculiarities of some of the 

 higher types. 



_ All this may be admitted as true, without in any way neglecting the fundamental 

 distinction insisted on by Von Baer between the grade of development and the 

 type of organization. 



It is to be observed with reference to the Anntdosa, that the difficulty of enun- 

 ciating propositions which shall be equally applicable to the Articulate properly so 

 called (Art/iropoda), and those lower annulose forms known collectively as Anmdoida 

 or Vermes, is still so much felt, as to render it doubtful whether these two great 

 divisions should not be raised to the rank of separate subkingdoms. This, at 

 present perhaps the most important question in systematic zoology, has already 

 been answered in the affirmative by J. V. Carus, Gegenbaur, R. Leuckart, Siebold, 

 and Vogt. 



The three first-mentioned of these naturalists regard the Eckinodermata as con- 

 stituting a seventh subkingdom. Of the propriety of separating this group from 

 the Ccelenterata no doubt can any longer be entertained, although Prof. Milne- 

 Edwards and a few other zoologists of repute still continue to unite these widely 

 different foims under the old name of Radiata. So long, however, as the arguments 

 brought forward by Prof. Huxley remain unanswered, the author can see no reason 

 to dissent from his conclusion, that the Eckinodermata, while forming a distinctly 

 circumscribed class, are nevertheless connected by true affinities with the division 

 Anmdoida. 



On the Mode of Death by Aconite. 

 By Edward R. Harvey, M.A., B.M., Oxon. 



Death by aconite has been attributed by different observers to its influence upon 

 each of the three vital organs, the heart, lungs, and brain. The following experiments 

 were made with a view of determining, if possible, the organ whose functions were 

 most directly interfered with by the poison. Fleming's tincture was always used. 

 In experiment 1, two minims of the tincture were injected beneath the skin of a 

 dog. In 2f koiirs after injection the dog died. There had been no convulsions, 

 no loss of consciousness, no apparent loss of sight, no change in the pupils, and no 

 disturbance of the respiration : the two marked symptoms were vomiting and great 

 prostration. On examination after death, the veins of the neck were seen to be 

 enormously distended. The heart contained blood partially clotted in both auricles. 

 The other organs were healthy. In experiment 2. on a rabbit, the heart was the 

 organ first affected (its pulsations falling in 5 minutes from 140 in a minute to 100, 

 and soon becoming laboured and irregular) ; the breathing then became distressed, 

 and just before death there were convulsions. Post-mortem examination directly 

 after death : — The veins of the neck and brain were distended with blood. The heart 

 gave, when exposed, two very slight quiverings, not to be called contractions ; all the 

 cavities contained blood. The other organs were healthy. In experiment 3, 

 similar symptoms during life and appearances after death we're observed. Experi- 

 ment .4. The heart of a frog having been exposed by removal of a portion of the 

 sternum, the pulsations numbered 60 in a minute, and were forcible and irregular. 

 After three or four drops of the tincture had been let fall into the thoracic cavity, 

 the pulsations became very rapid, feeble, and irregular, and soon could no longer 

 be felt: the beating here ceased: 10 minutes after death the heart was ao-ain 

 pulsating, though much more feebly than in another frog killed by pithing. "Ex- 

 periment 5. A young rabbit was killed by aconite, and another yoimg one by a 

 blow behind the ears. In the animal killed by aconite, there was a slight fluttering 

 movement of the heart, but there were no regular contractions, and galvanism pro- 

 duced no effect whatever ; in the other rabbit, the heart was contracting regularly 

 after death; and when all contraction had ceased, galvanism occasioned slight but 

 decided contractions. Experiment 6. Five minims of the tincture were injected 



