234 
University of California Publications in Zoology [ VoL - 27 
Description of larva. — Greatest length of head-and-body 28 mm. ; 
of tail 55 mm.; length of body contained 1.2 to 2.2 times in length 
of tail; external nares about equidistant between end of snout and 
eyes; distance between nares 1.2 to 1.9 in interorbital space; inter- 
orbital space 3.4 to 5.2 in length of head-and-body; eyes about 25 per 
cent of head-and-body length from tip of snout ; spiraculum sinistral, 
the aperture directed backward and slightly upward, center of 
aperture slightly behind midpoint of head-and-body; anus dextral; 
greatest depth of tail 2.5 to 3.2 in its own length. General coloration 
of upper and lateral surfaces of body dark brownish (not greenish), 
much mottled and with numerous dark spots 1 to 2 mm. in diameter, 
these having diffuse edges; middle of belly whitish iridescent, with 
slight pinkish tinge ; chin and throat region and sides of under sur- 
face finely mottled with light and blackish markings with a slight 
iridescence ; tail lighter than body, with blackish markings separating 
myomeres and with a light mottled pattern on caudal crests ; iris dull 
bronzy yellow. 
Labial teeth in f rows; uppermost complete, second divided, each 
short and the two separated by width of lower jaw; third of full 
width interrupted medially; fourth complete but slightly shortened 
laterally; fifth shorter than fourth; three rows of papillae on each 
side of mouth region, one row complete across lower border (fig. HH). 
Measurements of Adult Specimens of Rana aurora draytonii from California 
M.V.Z. 
No. 
Sex 
Locality 
Date 
Head-and-body 
length 
Length of head j 
Width of head | 
2 
O 
Interorbital 
space 
Forearm 
Hand 
Femur 
Tibia 
Tarsus 
Whole foot 
4411 
$ 
Santa Anita Canon, Los 
Angeles Co 
Apr. 10, 1909 
94.3 
33.0 
36.5 
10.5 
6.3 
26.3 
27.0 
49.0 
51.0 
28.5 
74.5 
7150 
$ 
Thornhill pond, 3 mi. se. 
Berkeley 
Feb. 18, 1919 
96.0 
34.0 
37.0 
11.0 
5.0 
25.5 
28.0 
52.0 
53.2 
30.0 
67.0 
5612 
9 
[near] Berkeley, Alameda 
Co 
Mar. 29, 1916 
96.3 
32.3 
38.0 
11.2 
5.4 
25.0 
28.2 
56.7 
53.6 
29.8 
82.0 
4409 
9 
Sierra Madre, Los Ange- 
les Co 
Apr. 10, 1909 
97.0 
34.0 
35.2 
11.2 
6.9 
25.8 
26.0 
52.2 
52.7 
26.8 
76.0 
4402 
9 
Sierra Madre, Los Ange- 
les Co 
Apr. 25, 1908 
May — , 1922 
106.0 
37.4 
39.0 
12.0 
7.5 
26.8 
31.0 
58.2 
55.2 
31.0 
81.0 
8577 
9 
Dublin, Alameda Co 
114.0 
39.0 
43.0 
13.4 
7.2 
27.0 
27.5 
66.0 
63.0 
35.0 
93.0 
7151 
d 
Thornhill pond, 3 mi. se. 
Berkeley 
Feb. 18, 1919 
78.5 
28.0 
27.5 
10.0 
3.5 
22.0 
22.0 
40.0 
44.0 
24.0 
55.0 
6111 
d 
Michigan Bluff, Placer 
Co 
Aug. 12, 1916 
81.5 
27.0 
29.0 
10.2 
7.3 
22.0 
21.5 
44.0 
47.0 
25.0 
58.5 
4401 
d 
Sierra Madre, Los Ange- 
les Co 
Apr. 20, 1908 
82.0 
28.1 
30.5 
9.7 
5.0 
21.7 
22.0 
40.6 
44.0 
23.3 
69.0 
4404 
d 
Sierra Madre, Los Ange- 
Ips Co 
Apr. 25, 1908 
84.0 
28.6 
28.6 
9.4 
4.0 
19.5 
22.0 
39.7 
42.1 
22.3 
65.0 
1 
Remarks on coloration . — The general tone of coloration is quite 
variable in the individuals of this species. Rana aurora draytonii 
alone among our California frogs (Ranidae) possesses considerable 
power of color change. This change can be rapidly effected, and once 
