SEPTEMBER 18, 1942 VoL. XX, PP PROCEEDINGS NEW ENGLAND ZOOLOGICAL CLUB TWO INTERESTING NEW SNAKES

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1 TRAVIS W. TAGGART SEPTEMBER 18, 1942 VoL., PP PROCEEDINGS OF THE NEW ENGLAND ZOOLOGICAL CLUB TWO INTERESTING NEW SNAKES BY THOMAS BARBOUR AND WILLIAM L. ENGELS THE senior author met the junior author, thanks to the kind offices of Professor R. E. Coker, at Chapel Hill, North Carolina, this spring. The junior author gave the senior author certain notes and two specimens, which form the basis of this paper, and kindly consented to this method of pub~ication, inasmuch as he was about to be called into serv1ce. During the course of the latter's studies of the fauna of the coastal islands of North Carolina, concerning which he plans to publish more detailed observations at a later date, these two interesting snakes were found. As is well known, the sandy, almost waterless, islands off the Carolina coast have a very limited and naturally somewhat highly specialized fauna and but relatively few forms have been able to adapt themselves to this highly rigorous environment. The first of the novelties may be called Lampropeltis getulus sticticeps subsp. nov. Holotype.-M.C.Z., 46,469, from the Knoll midway between Okracoke Inlet and Hatteras Inlet, Okracoke Island, North Carolina. Collected by W. L. Engels, 8th of June, This form may be distinguished at once from Lampropeltis getulus getulus by its broader and flatter head, heavily marked with white; large white spots are to be found on the

2 102 BARBOUR AND ENGELS-TWO SNAKES [ P.N.E.Z.C. Vol. labials and along the sides of the body; the anterior rings appear in the form of spots, and the chain-like pattern does not begin until well down on the body, and from then on the familiar pattern is composed of white bands averaging two and one half to three times as broad as the bands in the typical form; the three anterior spots are shown in the figure. These are followed by twenty-four bars on the body, whereas there are one bar and nine spots on the tail. There are twenty-one rows of scales, one hundred and four ventrals, forty-four subcaudals, although we suspect that the tip of the tail has been lost. Total length mm. The range of the typical form, extending as it does from southern New Jersey to northern Florida, is at great variance with the limited ranges of the immediately allied subspecies. Environmental conditions are certainly vastly differ:ent between the pine barrens of New ] ersey with their long, severe winters and the lush woods and hammocks of northern Florida. Doctor Carr informs us that in Florida, down to about Orange County, specimens ranging from typical Lampropeltis getulus getulus to typical L. g. floridanus are to be found in the same litter of young; whereas from Orange County south one finds typical floridanus only, the range of this form extending to central Dade County where intergrades between floridanus and brooksi are found. In southern Dade County only brooksi occurs. It is fascinating to ponder on why this should be, but utterly unprofitable. At first sight this might seem slender evidence for describing a new race, but the evidence that we deal here with a well-marked physiological form is so interesting that this fact alone would warrant its being named. For this snake, unlike all its allies, is not ophiophagous. Kept in captivity for a long time, as it was, it refused every sort of snake offered it for food and fed regularly on mice. Probably it was forced to do this on an island where, as far as is known, other snakes are absent and beach mice swarm. A glance at the figures will show how extraordinarily Pituophis-like

3 September 18) 1942 BARBOUR AND ENGELS-TWO SNAKES 103 is the head of our new form, and Pituophis, of course, is a rodent feeder. Whereas King Snakes normally twine about their prey, this snake has acquired the Coluber-like habit of seizing its prey and then dragging it to some position where it may be pressed to death with the body against some.firmly set object. Thus its feeding habits are those of a Black Snake and not of a King Snake. This fact was confirmed by repeated experiments of the junior author. The other new form may be called Elaphe quad.rivitatta parallela subsp. nov. Holotype.-M.C.Z., 46,468, from Sam Windsor's Lump, three miles from Beaufort Inlet on the Shackelford Banks, Carteret County, North Carolina. W. L. Engels' collection, 11 May, We have given this form its name on account of its obvious similarity to the recently described Elaphe williamsi Barbour and Carr, although equally obviously there is no direct relationship between these forms. The ancestor of this race is most certainly Elaphe quadrivitatta quadrivitatta or its progenitor. In the other form there is a question whether the ancestry is to be traced to Elaphe quadrivitatta quadrivitatta or to E. obsoleta confinis. There is nothing especially peculiar about the squamation of this snake. Its color, however, is very distinct. The straw-color of the typical form is replaced by a dull gray; the bands are evident; the lower lateral band on the posterior part of the body becoming a broad, dark zone three to three and one half scales wide; along the dorsum the upper lateral bands are connected by cross commissures which give the specimen in life a distinctly ladderback appearance, very like the aspect of Elaphe williamsi. Unfortunately, although the specimen was received in Cambridge alive, it was just about to shed, and the peculiar and conspicuous pattern is much

4 104 BARBOUR AND ENGELS-TWO SNAKES [ P.N.E.Z.C. Vol. less evident now, since a considerable portion of the body has desquamated. The junior author writes under date of May 18, 1942, as follows: "I agree that the differentiation of these forms must have been rapid, perhaps even more rapid than you suggest. As nearly as I can make out from a study of the Johnson and de Beaumont theory of development of these shore bars, these islands must be post-pleistocene in origin, and probably never were part of the mainland, or at most indirectly connected as now through Cape Henry and probably formerly also at the southern end of the series just below Beaufort, North Carolina. This is the view I am expressing in my paper on the Okracoke vertebrate fauna which is now ready to send away. It will appear in the American Midland Naturalist, probably in November." The senior author had suggested the possibility that these barrier islands had received their fauna at the time of the last glacial episode, when there was sufficient water tied up in the polar ice cap to have reduced the level of the ocean sufficiently to have made all these islands part of the mainland. In either event we have evidence here of how rapid may be distinct and fundamental changes of coloration and, in one case, modification of habits within a relatively short period of time. EPLANATION OF PLATES Plate VI. Upper figure, typical Lampropeltis g. getulus, M.C.Z., 34,071, from Rowland, Robeson County, North Carolina. lower figure, Lampropeltis g. sticticeps, type, M.C.Z., 46,469, from Okracoke Island, North Carolina. Plate VII. Upper figure, head and neck of Blaphe q. parallela. Type, M.C.Z., 46,468, from Sam Windsor's lump, North Carolina. lower figure, mid-body region of the same.

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