pi-hi ' di\id.'d 



un,-. ti,,. upp-r [MM, becomes associate*! u nli Hi.- organ of smell, to 



tin- rnlar^rm.-nt of which it contril.'. 



rose from th- 



lal.vrimh, as naso-pharyngeal pottage. This opens b 

 phar\n\ by means of the po^.-iinr nares. The lower part becomes 

 tin- secondary oral cavity, Th.- pai 



tli maxillary process is the palnf*-. \\hich later, when the dev- 

 infm ( ,f tli' bones of the head can !> traced, <ithe 



/ and the soft palate. 

 A small portion ; 1 fastm, which in \.>un^ embryos 



eraei tin- palate from m tVont backward anl unites oral and 

 na>al cavities (fig. 290 *), is preservtnl in mo-* rates and con- 



M it i ; "dus nasopalat > may be 



d through it from the na-al to tln-oi., In Man tin* 



diu-i closed daring embryonic 1 is preserved, 



however, in the palatal pro,-.--- . !' T IM- lony maxilla at theOOiresj' 

 iiii: j-lacc a vaeuity, the tiCl&ivtU, OCCUpi- 1 1 .y OODH8 



tissue, blood-vessels, and lu-rves. 



Where, tin- duct- - oy are present, there are f theil 



vu-inity the oryaiis of JACOBSON, concerning which the statement has 

 already U-.-n made that they are established very early as special 

 depressions of the two olfactory pit- In Man thi- or^an ^converted 

 into a narrow tnle, \vhieh lies a lit Me aliove the ea 

 "pin backward and -lightly upward close to 



the cartila^inou- jai'tition. ending Mindly" (ScHWALBE). In M 

 mals the organ is more highly <l.-v-lop.-d (!iir>. 

 rnvclop.-d in a special cartilaginous capsule (JACOBS* 'Iag0 



ves a special hraneh of tli.. olfactory nerve, wind 

 minates in a sensory epith.-lium, \\hieli agrees \ : the 



oltactori.i. |.' IV , ' i ) it opens into the 



heLrinninir of - s canal, which in this case remains open as 



a communication U-; ween nasal and - ies. 



1 riti-d the formation of folds as the second means of increasing the 

 intcinal >ui lace of the organ of smell. These are developed in 

 -Mammals (figs. 290, 291) and ii >n tin- latt-r.il walls of 



nasal chaml>-rs ; they run p.n "' : rom in 1 



iiackwanl; t h ii fiee margins grow downwartl. onsequenceof 



the forms which they a -MI me are called | natal turbiiiated 



processes, while tlie spaces between them are designated as upper, 

 ami /</>/ nasal passages. From the cai 



