136 SHUFELDT. [Vol. XVII. 



Supraoccipital {squama occipitis) has a small, round supra- 

 occipital foravien, the size of which varies in different indi- 

 viduals (diameter >^- 1 >^ mm.). 



The jugal bone is broadest in the rniddle, inasmuch as 

 its superior border develops a rather long, low, but distinct 

 process. The pterygoid bones are slender, becoming pointed 

 in front, where they offer but small articular facets, for articu- 

 lation with the palatines. 



The palatine bones are notably broad; pars plana of the 

 mesethmoid comparatively short, not coming out beyond the 

 external margin of the palatine bone, upon either side, when 

 the cranium is viewed upon its basal aspect. Vomer rudi- 

 mentary, and present as a slender osseous spine, or (in younger 

 individuals) completely unossified.^ 



2. Glaucidium passerinum (Linn.), 1766. 



(Plate XV, Figs. 4-6.) 



The auricular openings, which are without flaps, are, as well as the cra- 

 nium, symmetrical. 



The dermal parts of the auricular openings are small, sym- 

 metrical, and, comparatively speaking, placed high up, inasmuch 

 as their inferior extremities do not descend further down than 

 the lower border of the eye, the superior extremities ascending 

 to a point opposite the center of that organ, upon either side. 

 They are oval in form, with the longitudinal axis, in each case, 

 obliquely directed backwards. In an adult female specimen 

 (collected at Lillehammer, Dec. 9, 1876) the longest diameter 

 measured 6 mm., and the transverse diameter 4.5 mm. The 

 flaps were absent, and the skin did not create an elevated fold 

 about the borders. 



The ftostrils are small, with a comparatively broad space 

 between them, and are directed forwards, inasmuch as they are 

 situated in the fore part of the much swollen cere. Their ver- 

 tical diameters slightly exceed their transverse ones. 



The cranium, which is symmetrical, agrees, upon the whole, 



1 Literally translated this reads " fuldkommen hudagtigt," meaning " fully 

 membraneous." — R. W. S. 



