MONSTROSITIES. 



403 



generally very imperfect ; externally all the regions appear to be 

 anomalous, and the symmetry is imperfect or even effaced. 3. Parasitic 

 Monstrosities — the most imperfect of all, and generally inert, irregular 

 masses, composed of bones, adipose tissue, etc., destitute of umbilical 

 cord, and attached to the generative apparatus of the mother, at whose 

 expense they maintain an obscure parasitic existence, by means of a 

 vascular pedicle. 



The double monstrosities are divided into autositarian and double par- 



Fig. 87, 

 Symelian Monstrosity (Saint-Hilairk) ; Perosomus pseudoscelus (Gurlt): Pig. 



asitic. The first are composed of two individuals more or less intimately 

 united, and somewhat equal in development ; this inequality indicating 

 that they both have been equally nourished, and that their functions have 

 been alike complete. The second are composed of two distinct individ- 

 uals, very unequal in development, the smallest being the most imperfect ; 

 testifying that it, like a parasite, has lived at the expense of the other, 

 [It would appear that the triple monstrosities have not been met with in 

 jufficiently large numbers to establish a trustworthy classification. 



Celosomian Monstrosity (Saint-Hilaire) ; Schistocorntus Jissiventralis (Gurlt) : Calf. 



Each of the orders of Saint-Hilaire, like those of Gurlt, contains several 

 families, subdivided again into genera and species, according to their 

 iffinities, and which include all the monstrosities he had met with. With 

 regard to these families, it may be mentioned that among the single 

 lautositic monstrosities, there are the ectromelians {iV-pdu)^ to make abort, 

 i/oc, limb) in which we have a more or less complete deficiency in the 

 levelopment of the limbs, either anteriorly or posteriorly, and involving 

 me or more of these (Figs. 85, 86). 



