Rana grylio 373 



Female {From life, June 21, 1921). Upper lip from tympanum to snout 

 medal bronze also on top of head; upper parts olive citrine with a few dark 

 spots on the posterior back and groin. Upper part of legs saccardo olive with 

 cross blotches. Throat baryta yellow or better straw yellow. Where dorsal 

 color reaches light venter, so also on fore and hind legs there is one clear dull 

 green yellow or light dull green yellow. Venter marguerite yellow, also same 

 color on top of toes and fingers. Two patches on either side of throat and near 

 pectoral region, so prominent in the male, is light yellowish olive, not pro- 

 nounced as in male. No reticulations on venter except for faint reticulations 

 on under side of hind legs and the slightest indications on the groin region. 

 Rear of femur with one long band of sea foam yellow with line of quaker drab 

 below and dark quaker drab or black above. Iris with bright green yellow 

 ring around pupil. Iris black with lots of bright green yellow spots. Green 

 yellow outer circle around the black. 



Structural differences. The smallest male to show enlarging of tympanum 

 is 67 mm. or about one year after transformation. All the other of this series 

 are as follows: None of the other year-olds show secondary male characters 

 except one at 67 mm. where the tympana are enlarging; in some of the two- 

 year-olds (73-86 mm.) the tympana are enlarged and half of them have the 

 thumb discolored. Not until the three old stage (91-102) is reached do they 

 have the tympana very large and the intertympanic space much reduced. 

 The thumb is very well developed but never so swollen and stubby as in /?. 

 virgatipes, R. clamitans or R. catesbeiana. The males have more pointed 

 narrower heads than the females, are slimmer, have the intertympanic space 

 much reduced in males, thumbs discolored and somewhat swollen. The 

 females become larger than the males. 



Duration. It doubtless is shorter in this species than in R. sphenocephala 

 or species which begin ovulation earlier in the season. It is conceivable that 

 this member of the R. catesbeiana group like the R. catesbeiana might continue 

 amplexation for a long time. One R. catesbeiana male was recorded mated 

 with a dead female which doubtless died from a long amplexation. This is 

 the exception. Normally we would expect R. grylio to be of a short amplexing 

 group. 



Night or day. The immense choruses come at night and the vast majority 

 of mating must come at night. Some rainy or showery days or humid over- 

 cast diurnal weather may make them active in mating. We have no positive 

 records of mating being initiated by day though when crests come no doubt 

 some mating carries over into the day or begins about dusk or late afternoon. 



Amplexation. {Normal, abnormal). I have seen only two embraces of 

 this species, the first one pectoral, the second abnormal. No doubt the first 

 is normal. In the evening of April 29, 192 1, I have this entry: "In Long Pond 

 I heard R. grylio. The males were out in the middle of the pond among the 

 Pontederia. The R. grylios can easily be picked up with a flashhght. Some- 

 times a frog will move a foot or two or three. They rest on the surface. If 

 one keep quiet and put out the flashlight you can hear them jump once in a 

 while on the surface. Took a female R. grylio where there were several males. 



