96 TiUCHULOGlA MAMMAL1UM: 



successively more and more complicated sometimes by metamorphoses, and at others 

 without them. Having arrived at complete development, the period of decline commences; 

 for there is nothing stationary in their existence. There appears to be three distinct 

 varieties of hair of the head of man, referable to three as distinct periods of production, 

 viz: 



1st. The primitive hair, spoken of by Valentin and Bichat, as above quoted. These 

 fall off, mixing with the envelope of the foetus, and are never found except in the meco- 

 nium.* We have never been able to obtain any of these hairs. 



2d. The transitive variety, which succeeds to the primitive, and which is found upcn 

 the newly-born infant; but which generally falls out a few weeks after birth. 



3d. The permanent hair; if permanent may be called hairs which are being continually 

 renewed during life. 



4th. The hairs of puberty. 



It would be very interesting to ascertain whether the three first varieties are not pro- 

 gressive in the order of their perfection of organization, as they are in their order of time 

 of production. In order to determine this question, we have made several unsuccessful 

 exertions to obtain the pile of the first variety. ."With regard to the second, we think that 

 we have shown that it is less perfect than the third. (See title Follicle.) 



OF ACCIDENTAL HAIRS. Hair is, occasionally, developed in unusual places, as in the 

 cys.tis of ovaries on moles on navi materni on freckles on the mucous membrane of 

 the conjunctiva on the intestines on the gall bladder in the stomach on steatomatous 

 and encysted tumors on the tongue and in the uterus. 



Homer talks of the hairy heart of Achilles, and Pliny speaks of hair upon the heart, but 

 we have never witne.-sed any such phenomenon. Dr. Gross says that hair can he pro- 

 duced in unusual places by constant friction. (Elem. of Phys. and Anat,,p. 330.) (Sed 

 qusere ?) 



Of the Hair found in Ovaries. Among hairs that are denominated "accidental" 

 because they are found occasionally, only, being developed in unusual places, the most 

 remarkable are those discovered in the cystis of ovaries. Bichat gives the following 

 account of these anomalies : 



"A sack, sufficiently voluminous, contained a multitude of very distinct little balls, 

 resembling the excrement of sheep; they were formed of a white, greasy, unctuous sub- 

 stance, very different in aspect from common grease. On the internal surface of each of 

 these were planted a great many hairs, which the least movement was sufficient to 

 displace. The hair was black." He also found some hairs, entirely detached, which 

 were interlaced in various degrees of compactness in little balls. (Anat. Genl., v. 2, 

 p. 799.)t 



* Excrement noir et epais amasse dans les intestins d'un enfant naissant. 



f For ovary hairs see Meckl. Memoire sur les poils et les dents qui se develop accidentelleraent dans le corps. (See Jour. 

 Cuvnpl. au Diet, des Sci. Med., v. 4, pp. 122 and 217.) Also Bricheteax Obsr. de Kystes dermoides et pileux, <fcc. (Jour. 

 Compl. dcs Sci. Med., v. 15, p. 98.) Hairs have been found in the tosticlc.s. (Meckl.) 



