VENEZUELAN ORNITHOLOGY — FRIEDMANN AND SMITH 477 



As might be expected, the habits of the two races are similar, and, 

 as the birds could not be distinguished in the field, the following 

 observations are based on both forms. The Cantaura birds proved 

 all to be spencei, while those taken at Caicara were all assignable to the 

 race erythropus. Insofar as could be determined, their habits and 

 habitat preferences were identical, and it seems that the puzzling 

 existence of two very similar forms with such similar habits at stations 

 approximately 50 miles apart is probably explained by the isolating 

 effect of the intervening shortgrass savanna. However, to the north, 

 in the woods between San Mateo and Urica, the habitats of the two 

 forms appear to come in contact. Collecting at this point should 

 prove of interest. 



At first acquaintance, the name noctivagus appears to be well chosen. 

 The bu'ds begin to call in the late afternoon and decoy most readily 

 in that brief space of time before the woods become too dark to see. 

 Shortly thereafter the calling falls off, but individuals keep uttering 

 their clear whistled soy-so-la on and off throughout the night. The 

 collector-author had thought that the birds were rather nocturnal, as 

 the name and the nightly calls would suggest. However, a captive, 

 kept for several months, while very nervous and restless during the 

 day, slept so soundly at night that it often could be approached 

 without awakening. It seems that the night calls are of the same 

 nature as those of the domestic rooster, and that the tinamous are 

 not otherwise active at night. 



It is certain that both males and females call, as both were decoyed 

 in by whistled imitation of the call, were observed callmg, and were 

 collected in the act. However, of about twenty birds taken in this 

 manner, only one was a female. It appears that the females either 

 caU less or decoy less readily. The call of the female thus taken was 

 identical to that of the males, although the collector had the impres- 

 sion that the sound was a little weaker than usual. He reports that 

 the trachea of the male bears a slight bulbous enlargement, while 

 that of the female is unmodified. 



Inasmuch as Osgood and Conover (1922, p. 25) reported collecting 

 a male of a related species of tinamou (Crypturellus obsoletus cervini- 

 ventris) as it was flushed from its nest, it was thought that incubation 

 might be performed by the male. With this in mind, the present 

 male birds were examined, but were found to show no sign of any 

 brood patches. Furthermore, the female taken with a well-developed 

 egg in the oviduct revealed almost no brood patch either, and showed 

 only a very small denuded area well forward on the breast. However, 

 it was noted that the June birds, collected at the peak of the breeding 

 season, were actively molting the body feathers, with many pin- 



