1(1 JOHAN KI.1.1!. [SEC. ARCT. EXP. FRAM 



Tin- proportion mentioned above would in that case decrease to 

 about \. 



Tin- greale-t hreadlli aj>|ieai-s to he alinosl exactly at the middle, 

 by the sii|u-aorhital commissure. The outline is oval, hut in the front 

 i;it ||n- -in. uti it is narrower. The fern-most portion of the cranial shield. 

 1,,-t \\een tin- orhits and forwards, is tlat: farther hack the head is 

 rather markedly arched, and as is usual in this genus, there is a 

 -lightly rounded protuberance behind the eyes. The sides of the head 

 hehind the eyes are somewhat steep. 



l-'iu 1. Tlm-r cross-sections of Macropetalichthys Scheii IH-\V species. 

 in-ar tin- siipra-orliilal commissure. The centre figure at the point where the po.-t- 

 orl.ilal canal hranches o(T in the medial hone. Belo\\ , at Ilic jnolerior rml of tin- 



|ntorl.ital canal, \utnrul si/.-. 



Sculpt ii re. Tin- is only visible on a small part within the riijhl 

 orbit. At this spot the surface show> tine, slight crenulated tubercle-, 

 which behind appear to have a tendency to run together into longi- 

 tudinal ridges. 



Structure of the cranial bones. Mate I. lig. ">. shows a 

 microvropir >ection through the right side of the cranial shield, behind 

 the Mipraorbihil and infraorbilal canals. The portion of the section 

 \\hich appear- greatly enlarged in tig. Ii, i- from the thickest part, inside 

 tin- po-lorbital canal. 



Tin- -tin. -lure dearly show* agreement with thai of ('occosteiis di'd- 

 l>/rnx. The vascular canal -\-lein. ho\\e\ei. is wider and has thinner 

 \\all> than is the ca-e \\ilh the latter, a comparatively compact base- 

 ment layer al.-o ap|ears to be lacking. The bone cells are small, often 

 round, a^ in the ca-e i.f ( '<><-<-usli'iix. 



Characters of cranial shield. The separate bones ol 

 the cranial shield cannot be disl ingnished They must be assumed to 



