Rana virgatipes 451 



AUTUMNAL DISAPPEARANCE 



Published records and my own experiences carry their activities from 

 April 23-Aug. II. They come out earher than April 23 and must be active 

 at least two months after August 11. 



AFFINITIES 



(See R. grylio for comparison with that species). 



A funny episode or joke on the author shows how closely Rana grylio and 

 Rana virgatipes parallel each other in coloration. Three days after we first 

 heard R. virgatipes in the prairie near Chesser Island we went (July 15, 192 1) 

 at night to a wooded causeway to catch some we heard. ''Harry Chesser 

 caught one. Another put into the water after he put his light on it. We 

 heard several. Caught two frogs which we mistook for Rana virgatipes until 

 on the next morning we examined them closely. They are young Rana 

 grylio. Two of the three real R. virgatipes we saw, escaped." 



Boulenger (1920, p. 431) considers "The species does not exceed a length 

 of 60 millimeters from snout to vent, and may be regarded as a dwarfed form 

 derived from the R. catesbeiana type." 



Previous to 1921, we knew the distribution of Rana grylio to be from 

 Florida and Georgia to Louisiana, that of Rana virgatipes from New Jersey 

 to North Carolina and that of Rana septentrionahs from Canada and Maine to 

 northern New York and possibly to Catskills. One might have thought the 

 three a series with a gap between each species. Now we know the first two 

 to overlap. 



In coloration R. virgatipes looks most like R. grylio. In adult size it is 

 more like Rana septentrionalis but smaller or is possibly like a small R. 

 catesbeiana. At Lakehurst lake it reminds one of the water prairie form, 

 R. grylio; in the sphagnum strands and thickets of the Okefinokee it reminds 

 me of the peat lake species of Canada or beaver lake thicket form of Adiron- 

 dacks, namely Rana septentrionalis. In egg mass it is most like Rana septen- 

 trionalis, but in individual eggs unlike Rana septentrionalis, Rana clamitans 

 and Rana grylio it has no inner jelly envelope. The individual eggs are more 

 like the eggs of the film species Raria catesbeiana but the jelly is firmer. The 

 tadpole reminds one most of Rana grylio in coloration but it is more of the 

 Rana clamitans type. Like all of the Rana clamitans and Rana catesbeiana 

 type it winters over as a tadpole. It transforms at a size near that of RaTia 

 clamitans and may have a larger tadpole than that species. Therein it ap- 

 proaches R. catesbeiana, R. grylio and Rana septentrionalis. 



Cope 1891 (pp. 1018, 1019) writes of the species as follows: "This frog is 

 not nearly related to any species of the genus. It has some points of re- 

 semblance to R. temporaria as the short posterior legs and moderate web: 

 but the interocular space is much narrower, the vomerine teeth more anteriorly 

 placed, and there are no dermal folds. In coloration there is no resemblance to 

 any other species." Of course Rana grylio was not then known. If it is to 

 have an European counterpart might it not be that Rana virgatipes is rather a 



