Jan. 12, 1888] 



NA TURE 



245 



in association with Permian species of ferns and a 

 Walchia, seems however to place these Bohemian beds 

 on a lower geological horizon than the Gondwana series, 

 which have had their palitobotany studied by the same 

 pah^ontologist, Feistmantel, who investigated the plant- 

 remains of the Permo-Carboniferous of Eastern Europe. 



The rich fauna of Labyrinthodontia of the Gaskohle, 

 which, as was explained, Fritsch prefers to study under 

 the more comprehensive group of Stegocephali, is asso- 

 ciated with fish of the genera Ccratodus, Orthacanthus, 

 Pleuracanthus, 'Acanthodes, and Amblypterus, and also 

 with many species of /'rt!/<z'(?«m7/5', found elsewhere in true 

 Permian beds. Amongst the Invertebrates are Arach- 

 noidea, Julidae, Estheriae, and Anthracosiae. 



The part of the work now under consideration 

 is palacontological, and refers to some of the most 

 interesting of the many sculptured-headed, folded- 

 toothed Amphibia which preceded the Reptilia in 

 time. Several classificatory alterations, especially in the 

 grouping of the genera in families, are introduced, and 

 apparently with good reason ; and at the commencement 

 it will be noticed that the Microsaurii, Dawson, suffer, 

 and a new family, the Dendrerpetontidas, is founded. 

 Fritsch considers that the structure of the teeth of such 

 Microsaurs as Hylonovitis and Hylcrpcton^ prevents their 

 being associated in the same family with Deiidrerpeton, 

 the species of which have teeth strongly grooved from 

 the base, with simple irregular folds, the top being smooth : 

 the new family has, like the Microsaurs, amphicoelian 

 vertebrae. It is certainly remarkable how widely these 

 forms were distributed geographically during that long 

 period when so much of the present continental areas 

 was land. Fritsch describes two new species, and also 

 a thiid about the generic position of which there may be 

 some doubt, and which has a wonderful arrangement of 

 cranial bones behind the orbits. 



The most interesting parts of the work are now reached 

 and the author comes to the consideration of those extra- 

 ordinary Stegocephali which have such curious double and 

 multiple developments of the vertebral centra. The first of 

 the families of these groups is the DiplovertebridiC, and the 

 solitary form of it is carefully described. The characters 

 of the family are the doubly segmented vertebral centra 

 at the caudal end of the column, and a very decided 

 pitting of the surfaces of the bones of the extremities for 

 vascular canals. 



Fritsch avails himself of Cope's terminology ; and the 

 peculiar condition of the vertebral centra — the anterior of 

 the two segments carrying the spinous processes and the 

 ribs, the posterior not having any relics of arches, and 

 being plain — necessitates the arrangement of the species 

 with those whose vertebras are " embolomeri," The illus- 

 trations of the species on Plates 50 and 52 are admirable, 

 and their comprehension is assisted by the woodcut 

 diagrams placed in the context. 



Sparagmitcs lacerlinus, Fr., is placed amongst the 

 Archa:;gosauridae, and it will be observed (Plate 50, Figs. 15, 

 16) how the vertebral centra differ from those of the last 

 family. The centra appear to be broken up, and each has 

 two lateral and an inferior component, coming under the 

 division "rachitomi" of Cope. Miall's family Chaulio- 

 dontiais represented in the Gaskohle by a species, and the 

 preserved remains show the dissimilar teeth with a semi- 



Labyrinthodont structure ; the genus included is a familiar 

 one to English palaeontologists, and is Loxomina. The 

 last family, described in the book, has genera with highly 

 developed crania and a parietal foramen (which also 

 occurs in all these forms from the Gaskohle), and the 

 vertebrce are even more remarkable than in the other 

 families. In the Melosaurida; the caudal portion has the 

 centra embolomerous, whilst those of the fore-part of 

 the column are rachitomous ; the teeth are dissimilar, and 

 simply and irregularly folded. The supra-occipital bones 

 occasionally have strongly developed, backward project- 

 ing, curved processes {Sehnenhockem). The genus 

 Chelydosnurus, with a well-developed tarsus and a most 

 singular growth of chest and body plates, belongs to the 

 family. Sphenosminis, H. von Meyer, comes in here, and 

 the species S. Sternbcrgii, elsewhere a Muschelkalk form, 

 is found in the red sandstone of the Bohemian Permian ! 

 The new genus Cochleosaurus has a species which shows 

 the posterior hooks of the supra-occipital bones in per- 

 fection. 



The book which contains all this interesting matter will 

 be found of great value by students as well as by advanced 

 palccontologists, and the beauty of the illustrations leaves 

 little to be desired. The Geological Society presented 

 Dr. A. Fritsch with the Lyell Medal and Fund, and the 

 gift was mainly owing to the appreciation of his excellent 

 work amongst these Upper Palaeozoic, Permo-Carb. 

 fossils. The work is a great addition to the natural history 

 of the early Vertebrata. P. M. D. 



OUR BOOK SHELF. 



The Flora of Hoivtli. By H. C. Hart (Dublin : Hodges, 

 Figgis, and Co., 1887.) 



Mr. Hart enthusiastically describes the parish of 

 Howth as one with many attractions. He thinks that 

 as a seabathing summer retreat "its equal cannot be 

 found in Ireland" ; and he points out that it is invested 

 with archiieological interest by a great dolmen in the 

 demesne of Lord Howth, by the ruins of an early abbey 

 in the village of Howth, by the earlier church or chantry 

 of St. Fintan's on the Sutton side, with its holy well, and 

 by the ancient castle, called Corr Castle, of the Barons of 

 Howth. A little way from the shore is Ireland's Eye, 

 with the remains of a church of the sixth or seventh 

 century. For the ornithologist, the entomologist, and the 

 marine zoologist, Howth, according to Mr. Hart, provides 

 much material for study. These things, however, he 

 notes only by the way ; it is with the flora of Howth that 

 he is especially concerned. For this he claims attention 

 on two grounds : (i) because several of the species found 

 are rare ; (2) because it does not often happen that so 

 many forms exist in so small a space. Mr. Hart has 

 taken great pains to make his account of his subject 

 complete and readily intelligible, and the book ought to 

 be of considerable service to local botanists and tourists, 



Mineralof^y. By Frank Rutley. Third Edition. (London : 



Thomas Murby, 1887.) 

 We are glad to welcome a third edition of this excellent 

 manual, which forms one of Murby's "Science and Art 

 Department " series of text-books. The materials of the 

 little work are arranged with great clearness, and the 

 descriptions of minerals are invariably simple and pre- 

 cise. Nearly the whole of the chapter on crystallography 

 has been re- written, and other alterations have been made 

 to fit the book for the present requirements of students. 

 More than fifty fresh woodcuts have been added. 



