MALFORMATIONS. lUJ 



body or the development of an isolated group of segmentation 

 cells. In asymmetrical duplicity one body is rudimentary or 

 under-developed, (the parasite), and the other body develops 

 normally or nearly so, (the autosite). The parasite alwayd 

 remains attached to the autosite or is included by it. Parasitic 

 duplicit)^ ma}' occur in any region. Thus the parasite rnay pro- 

 ject from the orbit, mouth, shoulder or it may be included in 

 the thoracic or abdominal cavities. 



iiui.riPLicnv is the name applied to designate the develop- 

 ment of more than two separate individuals in a single chorion. 

 }\Iultiplicity is of rare occurrence. One single case has been 

 authentically reported in the human in the form of a tricephalus. 



