32 
THE BIRDS OF AUSTRALIA 
4. Cave Owl Tyto novce-hollandice troughtoni sub.-sp. nov. 
troughtoni —Ellis Le G. Troughton, Mammologist, Australian Museum, 
Sydney. 
Distribution. —Nullarbor Plain (South Australia). 
Notes ,—Usually singly or in pairs, frequenting the Nullabor Plain. 
It roosts and nests in blow-holes and underground caves, venturing forth 
at night in search of prey. Food: small lizards, small mammals, and 
rodents. 
Nest. —In a blow-hole or an underground cave. 
Eggs. —Not recorded. 
Description. —Type, adult female, collected at Ooldea, East-West 
Line, South Australia, by Messrs Troughton and Wright on 16 October 
1921, Registered _Number 026568, Australian Museum, Sydney. Differs 
from the t_vpical Masked Owl ( Tyto novce-hollandice ) in its smaller size, 
lighter coloration on the back, and in having fewer spots on the under¬ 
parts. Measurements: total length, 460 mm.; wing, 326; culmen, 26; tail, 
161; tarsus, 75. 
Females of the Masked Owl are noticeably larger and darker than 
the males; the type of the Cave Owl, however, which is a female, is com¬ 
parable to an average-sized male of the Masked Owl. 
5. Tasmanian Masked Owl Tyto castanops Gould 
cas'-tan-ops —Gk, castanon, chestnut; Gk, ops, face. 
Distribution. —Tasmania. 
Notes. —Also called Chestnut-faced Owl. Usually singly or in pairs, 
frequenting forests of large and thinly scattered trees skirting open coun¬ 
try. It is similar in habits and economy to the Masked Owl. The sexes 
differ considerably in size, the female being larger, more powerful, and 
darker in coloration than the male. 
Nest. —In a hollow in a tree or in a cliff. 
Eggs. —Not recorded. 
6. Grass Owl Tyto longimembris Jerdon 
lon-gi-mem -bris —L., longus, long; L., lnembrum , limb. 
Distribution— Northern Territory, Queensland, New South Wales, 
and \ ictoria; also occurs in India, China, the Philippine Islands, New 
Caledonia, and Fiji. 
S ! ngly ’ frec l ueilt ing grass-lands, chiefly of the coastal 
tn ‘‘LZt’’ y m h , aS ' 3Cen , recorded of its habits - It rests'during the day 
insect! a„d Sags “ tUSS ° Cl ‘ ° f grass ' Food: rodents - >“*■ 
Nest . — Under or in a tussock of grass, 
to J uly^ S ' USUaHy w hite, oval in form. Breeding-season: May 
