204 Scientific Intelligence — Zoology/. 



following morning there was another shock, about 30 mintues past 9 

 o'clock : it was more severe, and continued for more than 40 seconds. 

 The noise, which might be compared to that of a heavily loaded waggon, 

 ran from the south to the north. The same shocks were felt on the 

 roads of Rennes, Nantes, and Jeze, at some distance from Corps-Nuds.* 



ZOOLOGY. 



7. On the Structure and Development of a newly discovered Animalcule of 

 the Human Skin, the Entozoon folliculorum. By Erasmus Wilson, Esq., 

 Lecturer on Anatomy and Physiology at the Middlesex Hospital, — While en- 

 gaged in researches on the minute anatomy of the skin, and its subsi- 

 diary organs, and particularly on the microscopical composition of 

 the sebaceous substance, the author learned that Dr Simon of Berlin 

 had discovered an animalcule which inhabits the hair follicles of the 

 human integument, and of which a description was published in a me- 

 moir contained in the first number of Miiller's Archiv, for 1842. Of this 

 memoir the author gives a translation at full length. He then states that, 

 after careful search, he at length succeeded in finding the parasitic ani- 

 mals in question, and proceeded to investigate more fully and minutely 

 than Dr Simon had done the details of their structure, and the circum- 

 stances of their origin and development. They exist in the sebaceous 

 follicles of almost every individual, but are found more especially in 

 those persons who possess a torpid skin ; they increase in number during 

 sickness, so as in general to be met with in great abundance after death. 

 In living and healthy persons, from one to three or four of these en- 

 tozoa are contained in each follicle. They are more numerous in the 

 follicles situated in the depression by the side of the nose ; but they are 

 also found in those of the breast and abdomen, and on the back and loins. 

 Their form changes in the progress of their growth. The perfect animal 

 presents an elongated body, divisible into a head, thorax, and abdomen. 

 From the front of the head proceed two moveable arms, apparently 

 formed for prehension ; and to the under side of the thorax are attached 

 four pairs of legs, terminated by claws. The author distinguishes two 

 principal varieties of the adult animal ; the one remarkable for the great 

 length of the abdomen and roundness of the caudal extremity ; while 

 the other is characterized by greater compactness of form, a shorter ab- 

 domen, and a more pointed tail. The first variety was found to measure 

 in length, from 1-lOOth to the 45th, and the second, from the 1-lGOth to 

 the 109th part of an inch. 



8. Discovery of a Mycoderm which appears to constitute the disease known 

 by the name of Plica Polonica. By Dr Gunsbourg of Breslau. — M. Guns- 

 bourg's researches have been made on two different specimens, both ob- 

 tained from women, and which differ only in the greater or less degree 

 of resistance in the agglutinative mass. He found this mass formed, 



Ist, Of a great number of epidermic cellules in juxta-position, of more 



* From L'Institut. No. 517, p, 404. 



