- 3 



paired intermaxillary gland, which is homologous to that of amphibians and opens ventrally into the 

 oral cavity. A similar gland also was in Eusthenopteron according to Jarvik but was significantly 

 smaller and was located in a small depression (fossa apicalis, see fig. 5/ which occupied the 



—fig. 2— 

 extreme anterior part of the ventral surface of the ethmoid and opened into the po 

 oral cavity by a canal crossing the vertical toothed plate of the vomers (iv. p). 

 great phylogenetic significance to the latter canal in comparing it with the canal 

 and Anura. Starting from the presence of the ethmoidal section of the cranial cav 

 the conclusion was made that the structure of the ethmoidal part of the brain diffe 

 and Osteolep i formes. 



sterior part of the 



Jarvik granted 

 s of labyr i nthodont s 

 ity in Porolep i s , 

 rs in Porolep if ormes 



Osteo 

 Ec tos 



Recent i 

 lep if ormc 

 teorhach i 



the p 



Porol 



resence 

 ec i s . or 



this 

 funct 

 assum 

 Judg i 

 Pande 



fish beg 

 ional s i 

 pt ion th 

 ng by th 

 r ichthvs 



these 



poss 



organ 



f i shes, 



ble that 



of balar 



es t i ga 

 Plat 

 (Thorns 

 the et 

 e othe 



beh i n 

 f i cane 

 the 

 arro 

 d Plat 

 e., th 

 e eth 



suppl 



tions ha\ 



phal i ( 



on, 1964; 

 hmoidal c 

 r hand, i 

 d the lev 

 e of the 

 ter i or pc 

 aperture 

 ycephal ie 

 e e t hmo i c 

 oidal cav 

 ement i ng 



; shown 

 ithys ( 

 , and a 

 -an ial 

 3 doubt 

 ;1 of t 

 sthmo id 

 ■t ion 

 uf thee 

 ithys . 

 il cavi 

 ity is 

 the can 



that 

 Vorob 

 ppare 

 cav i t 

 ed by 

 he an 

 al ca 

 f the 

 ran ia 

 only 

 ty c 

 analo 

 also 



a broa 



eva, 1 

 ntly Gl 

 y has a 



Kulczy 

 terior 

 vity of 



bra in 

 1 cavit 

 olf ac to 

 uld not 

 gous to 

 f the 1 



d 



959) 



ypt° 



ternasal wall is characteristic eve 

 , Panderichthvs (Vorob'eva, i960, 1 

 E. 



yptopomus (Jarvik, 195^ ' • ^ or * ne ^ ' r: 



lso been established (fig. 3> 2). Its 



cki (i960) who assumes that the cranial 



walls of the eye sockets (fig. 4, 3, " ) 



lungfishes is still unclear. However, 

 (fig. 4, 3> hem) is located in it is no 

 y in the posterior section ot the sphen 

 ry canals could pass in the interorbita 



include the hemispheres of the brain. 



the rostral cavity of La t i mer ia and se 

 ateral line (Vorob'eva, 1962, p. 20). 



n of some 



962), 



t two genera, 



ex i stence i n 



cav i t y in 

 . The 



Jarvik ' s 

 t jus t i f i ed. 

 ethmoid of 

 1 area of 



It is 

 rved as an 



As far as the cavum internasale and fossa apicalis are concerned, Kulczycki and Thomson are 

 inclined to consider them homologous and the only receptacle of the large front teeth of the lower ja^ 

 This possibly does not diminish the significance of these pits since the teeth or toothed spiral is 

 not developed at the anterior end of the lower jaw in all Rhipidistia. 



-p. 1359- 



ub 



s i z 



soc 

 not 



the 



■'la 



The 



i n 



/idi 



of the nasal cavities also is suggested as a means of distinguishing two types of 

 : the character of the walls, the presence or absence of branches and projections 

 e number and position of openings of blood and neural canals, the position and 

 openings joining the nasal cavities with the external environment, with the eye 

 oral cavity and in particular the position of the nares and the size of the choanal 

 ntation of the great phylogenetic significance of the details of the structure of 



-fig. 3— 

 o sections can distinguish even close forms: Pander ichthys . Eustenopteron . 

 tycephal icht hys (Vorob'eva, 1 962 ) and, conversely, can coincide in representatives 

 hthys ) . Thomson considers it generally impossible on the basis o 



rue tu 

 p i d i s 

 them, 

 hes a 

 th t 

 s pr 



t i 



th« 

 nd 

 he 

 eser 



isal 



:epha 



alt 



it 

 thi 



ce t 

 gh a 

 impc 

 u t gr 



of both 

 f paleort 

 Th 

 Ec tosteor 



groups 

 olog i cal 

 eref ore , 

 hachis, 



compare the sections of the nasal capsule with the divisions of the nasal 

 Yentro-lateral depression for example is found even in Eusthenopteron and 

 aible to decide whether it corresponds to the outgrowth of the olfactory sac and whether 

 «/th contains Jacobson's organ. 



The position of crests and processes in the nasal cavity can also coincide in representatives 

 of both groups. In particular, the processus intermedium or its homolog is as much pronounced in 

 Porolep i s (Kulczycki, i960) as in Eusthenopteron (fig. 2, I, pr. im), is somewhat altered in 

 Ectoste or hach i s (Thomson, 1964) and is lacking in Pander icht hys (Vorob'eva, 1962). Therefore, the 

 assumption by Jarvik that the rostrale laterale in Osteolep i formes always has this process in 

 distinction from Porolep i formes is without confirmation. At the same time, in Pander ichthys there is 

 a similarity of the rost ro-caudal crest characteristic ot Porolep i s (fig. 2, 2, ri. w. al) and a 

 small lateral depression re. 1, corresponding in position to recessus lateralis. 



The interpretation of the processes of the nasal cavity and the homologizing of them with 

 processes in amphibians has been the object of doubt. Kulczycki opposes the homology of the rostro- 

 caudal process of Porolep i s (crista subnarina according to Kulczycki) with ;h» processus ros trocaudal i s 

 of Urodela and considers that its appearance is connected with the passage of the suborbital sensory 

 and postnasal canals. He does not agree with the presence in Porolep i s of Seydel's process (fig. 2, 2, 

 pr. S) and points to the fact that if the crista subnarina is homologous to the processus rostrocaudal i s , 

 then the small choanal process, appearing as its continuation, occupies a different position from that 



