INTRODUCTION. 



TIIK history of the <l-\ - lopn cut .f th" individual, or < ! 



bryology), is the science of the growth <f an organism] 



scribe^ the morphological chants uhich :in orpini-m ja>s s through 

 from its origin in tin- ovum up to its comj)l t- mat nrity, and present** 

 thtsi-in their natural connection. \\V C <1 tli'- tVrtili- 



of the ( 'gg-o 11 as tin- In -ginnin;: of the process of devt lopiin li 



\'-i-trlirat. B, afi it :il>> is for all the rest of the higher animals. 

 In ^ivin^ an account of the changes of the r^'-rrll. \\liicli 1. 



with fertilisation, one may choose between two different m< th.il>. 



.online to one meth< <1 a particular or^Miism is mad- the i 

 of the accounu an<l (me i Bcribes the ciianir' s which its p-nn umli-r 

 goes from the moment of fertilisation onward, from hour to hour-, 

 and from d.-.y to day. It i.> in this way that the embryology of the 

 Chick IIMS be- n worked out by ( '. Iv \"\ l;\i:i; in hi> i-la ical j 

 and by FOSTKK AND BALFOI u in their " Kl'ii;-m> <>f Embryology." 



ThiN inetlK'd lias the ;id\ a lit air- that th']-eadtr ac(|uii'.>a vi.wi.f 

 the total condition of MI or^ani-m in tlie st |>ai-ate .-ta!_ r 's of it^ 

 lopment. 



A book of that kind is >p. cially ^uitaiile for Mich ^ 

 doire to aci|iiaint t hemseivi s, by tin ir own oh^ervatioii. with the 

 embryology of a single animal, as, for xample, the (.'hick, by 

 repeating the in\ e-tiirat ions of ( .thr>. h is. on the contiai-x. 

 adapted to those \\ ho wish to acquire a connecied \i.\\ of tin- 



development of the separate ori:an-. a> the eye, the h. ai-t. tin- brain, 



( tc. For the formation of these will of eour>e be t ivati d of at dill'. 

 placo in d >ci-ibiiiir ynunirer and older einbryo>. In order t- 

 a iTeiu-ral >Ulvey of the collide of d-v lopn.enl of an or^an, tlie 

 rt ;,der mu>t consult various places intln -k. andcolhc; 



bim>elf what relat. - to the Mib;. 



I'd- beginner-, and for the HIM ds of theoretical instruction ir 

 Embryology, the second mei In d loinmrnd.- it>elf. in which the 

 organs are con>idered in >ucct'->ion. -arh tor it>elf. and tin- changes 

 \vliich a single organ has to pa-s thicu-h dining d v< lopi 



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