37 



the third is the typical JY. typhlops (Stirling), from Central 

 Australia. It appears certain that the embryo could not 

 have belonged to either of the Western Australian specimens, 

 but beyond that it seems impossible to determine its origin. 



The state of preservation of the specimen is not very 

 good, and subsequent microscopical work would not appear 

 to hold out very great promise, but considering the great 

 rarity of embryos of Notaryctes it is well to place on record 

 the external characters of even a single embryo, and one, 

 moreover, which lacks a history. 



The embryo measures 10 mm. from the vertex to the 

 most distal point of the flexed caudal extremity. 



•;'.''• ' '.''■ •-•'rSM- ■'■''' ''''^•U:^0^^^- : '' :. '.'■:'':':' 



Fig. 2. 



Notoryctes typhlops. 



Front view of the head to show the 



features of the rhinarium. 



The head is but little flexed on the trunk, but the caudal 

 extremity is flexed in the pelvic, and, again, in the sacral 

 region, so that the tip of the tail is brought beneath the chin. 



No trace of hair can be detected, nor are there any skin 

 elevations or sensory papillae present. The eye is well marked 

 as a conspicuous patch of black pigment which shows clearly 

 beneath the covering epitrichium ; no trace of eyelids or 

 accessory structures are visible. 



The external auditory meatus is situated somewhat far 

 back, behind and below the eye spot; it is surrounded by a 



