Gen. MEGHYPENA Grt., 1873.

65. edictalis Walk. Canada to Middle States.

vellifera Grt.
lentiginosa Grt.

Gen. LOMANALTES Grt., 1873.*
Type: L. latulus.

66. eductalis Walk. Nova Scotia to Texas.

lætulus Grt.

Gen. HYPENA Schrank, 1802.

Type: H. rostralis.

67. californica Behr. Calif.; Vancouver; Brit. Col. 68. modesta Sm. Los Angeles, Calif.

69. decorata Sm. California; Vancouver.

70. germanalis Walk.

evanidalis Rob.

humuli Fitch nec Harris.

var. olivacea Grt. (pale form).

var. albopunctata Tep. (dark form).

Gen. PLATHY PENA Grt., 1873.

71. scabra Fabr.

humuli Harris.

erectalis Guen.

var. subrufalis Grt. (rufous form).

The Reptilian Order Cotylosauria.

By E. D. Cope.

(Read before the American Philosophical Society, November 15, 1895.)

The characters of this order are as follows:

Quadrate bone united by suture with the adjacent elements. Temporal fossa overroofed by the following elements: Postfrontal, postorbital, jugal, supramastoid, supratemporal, quadratojugal. Tabular bone present. Vertebræ amphicœlous; ribs one-headed. Episternum present. Pelvis without obturator foramen.

This order is of great importance to the phylogeny of the amniote

*In the Bull. Brook. Ent. Soc., Vol. vii, 4, Mr. Smith says of his new Bomolocha that "it is nearest to the latulus variety of deceptalis." Nowhere in the Revision can I find mention of this remarkable variety of deceptais, pr. syn. or pr. var. I do not know what to make of the omission. Now, in the Revision, Mr. Smith adopts Lomanaltes and says that the insect "does convey a somewhat distinctive impression." As in Agrotis opipara and Oncocnemis riparia, etc. Mr. Smith's synonymy is here not full; the omitted references tell against me and here cover up a remarkable error of judgment on his part.

Vertebrata. The structure of its temporal roof is essentially that of the stegocephalous Batrachia, while the various postorbital bars of the amniote Vertebrata are explained by reference to the same part of its structure.

The relations of the opisthotic and paroccipital bones in the later orders are apparently explained by their structure in the Cotylosauria. I have identified the element which intervenes between the exoccipital and the supratemporal in the Lacertilia with the distal part of the opisthoticoparoccipital element in the Testudinata, retaining for it the name of paroccipital. Thinking that I have confounded this element with the opisthotic, Baur differs with me,* and calls the element in question the squamosal. My belief in the position taken was based on the character of this region in the Pythonomorpha, where the paroccipital extends proximad to the petrosal, and nearly or quite to the opisthotic, which it does not do in the Lacertilia, a fact not sufficiently regarded by authors generally. I assumed, in consequence of this structure in the Pythonomorpha, that the single element in the Testudinata which extends from the supraoccipital to the quadrate, really includes two elements, the opisthotic proximally and the paroccipital distally. This view is confirmed by the fact that the two elements in the Cotylosauria are distinct. I have been able to locate the semicircular canals definitely in the genera Empediast and Chilonyx, and to fix the position of the opisthotic, petrosal and epiotic bones. In adults these elements are coössified, but they appear to be separated by suture from the exoccipital and from the paroccipital. The latter is a long bone and supports the quadrate exclusively, the exoccipital being separated by a considerable interval. The form of the quadrate is that characteristic of theromorous Reptilia and Batrachia. It is distal in position and short, not reaching the cranial box by its proximal extremity, with which it is connected by the paroccipital, and by the elements of the temporal roof.

The palatal elements in this order are more or less in contact on the middle line, and the pterygoids diverge abruptly from this point, and return to the quadrate. The occipital condyle is single, and does not include exoccipital elements (unknown in Elginia).

Intercentra are present in Pariasauridæ, Diadectidæ and Pariotichidæ, and they are wanting in Elginiidæ. The hyposphen-hypantrum articulation is present in the Diadectidæ, but is wanting in the Elginiidæ and Pariasauridæ.

The scapular arch is best known in Pariotichidæ, Pariasauridæ‡ and Diadectidæ. In the two former there is a T-shaped sternum, over which are applied the median extremities of the clavicles; and there are a welldeveloped coracoid and præcoracoid. In Diadectidæ || (probably genus Empedias) the episternum is articulated by suture with the clavicles.

*American Naturalist, 1895, p. 998.

† Proceeds. Amer. Philos. Soc., 1885, p. 234.

Seeley, Philos. Trans. Roy. Soc. London, 1888, p. 89; 1892, p. 331.

| Cope, Proceeds. Amer. Philos. Soc., 1883, p. 635.

In the Proceedings of this Society, 1892, p. 279, in a paper on "The Phylogeny of the Vertebrata," I wrote as follows: "Moreover, the Pelycosauria and the Procolophonina have the interclavicle, which is an element of membranous origin, while in the Prototheria we have the corresponding cartilage bone, the episternum. This element is present in the Permian order of the Cotylosauria, which is nearly related to the Pelycosauria." The examination of the sternal region in Pariotichus has led me to the conclusion that the episternum and interclavicle are present and fused together in that genus, and also to the belief that the episternum is present in the genus Procolophon. The structure is generally similar in the two genera, and I think that Seeley is in error in determining the element in question in Procalophon as the interclavicle only. Gegenbaur pointed out in his Comparative Anatomy the different, i. e., membranous origin of the interclavicle of the Lacertilia, but he included it with the episternum under the same name. The true episternum is not present in the Lacertilia. It is present in the Sauropterygia and Testudinata and probably in all the orders with one postorbital bar, or Synaptosauria, while it is wanting in most or all of the Archosaurian series, and in the Squamata. Whether the element I have referred to in the genus Naosaurus as interclavicle, is that element or the episternum, must remain uncertain until I can see it in place. Its edges are thin, as in the interclavicle of the Lacertilia. Of course the reptilian order which is in the line of ancestry of the Mammalia will have an episternum, and not an interclavicle only. The Stegocephalia among Batrachia possess an episternum, with, perhaps, an adherent interclavicular layer as in the Testudniata.

Seeley describes four sacral vertebræ in Pariasaurus. In Empedias there are but two. The pelvis is without obturator foramen. The humerus has an entepicondylar foramen. The tarsal and carpal elements are incompletely known.

There are palatine teeth in Empedias and Pariasaurus, but none in Elginia.

The inferior surface of the cranium is known in Elginia, Pariasaurus, Empedias and Pariotichus, and has been described as to the first three genera by Newton, Seeley and myself. Pariotichus displays generally similar characters. There is a pair of posterior nares, and a pair of zygomatic foramina, but there is no palatine foramen. The palatine elements meet on the middle line, but gape behind. The vomers (prepalatines) are distinct, and are well developed anterior to the palatines. The ectopterygoid is large and has a prominent posterior border. I have stated that in Empedias there are teeth on the vomer. Better preserved specimens of Pariotichus show that the teeth are really borne on the edges of the palatines, which are appressed on the median line in the former genus. Similar palatine teeth are present in Pariasaurus, but are wanting in Elginia. Teeth are also present on the posterior edge of the ectoptergoids in *Philos. Transac. Royal Society, 1889, p. 275, Plate ix, Fig. 9.

Pariasaurus and Pariotichus, but not in Elginia or Empedias. A character of the American genera is the weakness of the attachment of the basioccipital to the sphenoid. The basioccipital is lost from the only known specimen of Elginia, and the sphenoid projects freely below it in Pariasaurus. The roof of the mouth in this order is a good deal like that of the Lacertilia, lacking the palatine foramen.

The order Cotylosauria was defined by me in the American Naturalist for 1880, p. 304, and in 1889 (October). In 1889 (Transac. of the Roy. Soc. London, p. 292), Prof. Seeley gave it the name of Pariasauria. In my Syllabus of Lectures on Vertebrate Puleontology (1891, p. 38), I arranged the group as a suborder of the Theromora. In 1892 (Trans. Amer. Philos. Soc., p. 13, Pl. i), I again regarded the Cotylosauria as an order, and described the characters of the skull in three of the genera, and gave figures of them.

Seeley has objected to the reference of the genera Pariasaurus and Empedias to the same order, on the ground that the elements connecting the supraoccipital and the quadrate rest on the occipital elements in the latter, while they are elevated above them in the former. This character would not, however, define orders, as both conditions are found in the Lacertilia; but might distinguish families within an order. However, Seeley's description and figure of the occipital region in Pariasaurus bainii* show that the structure only differs from that of the Diadectidæ in the presence of a large foramen between the supraoccipital and exoccipital bones on each side.

Seeley has also proposed to include Eryops in this order. But Eryops is a true batrachian with two occipital condyles, and a large parasphenoid bone. The dental structure is like that of Actinodon, and the vertebræ are of the rhachitomous type, which is unknown among Reptilia.

The known species of the Cotylosauria range in dimensions from that of the South American Caimans (Chilonyx, Pariasaurus sp.) to that of the smaller Lacertilia, e. g., Eumeces quinquelineatus (Isodectes and Pariotichus sp.). They range from the Permian to the Trias, inclusive, and have been found in South Africa, North America and Scotland.

This order embraces at present four families, which are distinguished as follows:

I. Teeth in a single series.

Teeth not transversely expanded; vertebral centra with surfaces only ossified; no hyposphen..... ..... Elginiida.

Teeth not transversely expanded; vertebral centra ossified; no hypo-
sphen......
......Pariasauridæ.

Teeth with the crowns transverse to the axis of the jaws; vertebræ ossi-
fied and with a hyposphen-hypantrum articulation....... Diadectidæ.
II. Teeth in more than one series in (one or) both jaws.
Teeth with cylindric roots; vertebræ ossified

.Pariotichida.

Philos. Trans. Roy. Soc., 1892, p. 326, Pl. 18, Fig. 2.

PROC. AMER. PHILOS. SOC. XXXIV. 149. 3 D. PRINTED FEB. 8, 1896.

These families embrace the following genera.

ELGINIIDÆ.

This family includes but one genus, Elginia Newton.

ELGINIA Newton.

Philos. Trans. Roy. Soc. London, 1893, p. 489.

Supraoccipital and tabular bones well developed on the superior surface of the cranium, the latter produced into a horn. Teeth pleurodont, crowns distinct from shafts, compressed, serrate. Posterior nares anterior. Pterygoids divergent (Newton).

The above characters are derived from Prof. Newton's description and figures. His epiotic bone is my tabular, and his squamosal is my supramastoid. It is probable that the superior border of the orbit is formed by the frontal bone, which separates the postfrontals from the prefrontals. The skeleton is unknown. Newton refers this genus to the "Pariasauria."

ELGINIA MIRABILIS Newton, loc. cit., p. 473, Pl. 37-40.

Elgin sandstones (Lower Trias ?), Scotland.

PARIASAURIDE.

Three genera are probably referable to this family, which differ as follows:

Teeth on the vomer and palatine bones; vertebræ shallowly biconcave.

Vertebræ deeply biconcave...

Palate toothless; ? vertebræ.

Pariasaurus Seeley.

...Anthodon Owen. Tapinocephalus Seeley.

The above characters I derive chiefly from Seeley.

PARIASAURUS Seeley.

Philos. Trans. Roy. Soc. London, 1888, p. 95. Owen, Nomen Nudum ; Foss. Rept. S. Africa, Brit. Mus. 1876, p. 6.

PARIASAURUS SERRIDENS Owen, Foss. Reptilia South Africa Brit. Mus.,

1876, p. 6, Pls. vi, vii, viii, Figs. 1, 2. Seeley, Trans. Roy. Soc. London, 1888, p. 75, Pl. xvi.

Permo-Trias of South Africa.

PARIASAURUS BOMBIDENS Owen, l. c., p. 9, Pl. viii, Fig. 3, Pls. ix, x, xii. Seeley, Philos. Trans. Roy. Soc., 1888, p. 59, Pls. xii, xiii, xiv, xv; 1. c., 1892, p. 315, Pl. xx.

Permo-Trias of South Africa.

PARIASAURUS BAINII Seeley, Philos. Trans. Roy. Soc. London, 1892, p. 322, Pls. xvii, xviii, xix.

Permo-Trias of South Africa.