

Bihliofjraphical Notice. 287 



BIBLIOGHAPHICAL NOTICE. 



Monograph of the Turbellarians, — 1. Rhabtloccelida. By Dr. 

 I Ludvvig vox Graff, Professor of Zoology at the Forestry Insti- 



j tute, Aschaffenlmrg. Leipzig : W. Engelmann, 1882. [Mono- 



grapJiie der Turbdlarien <Jv.] 



This handsome folio volume of 442 pages is accompanied by an atlas 

 of twenty plates of admirably drawn figures, and is further illus- 

 trated by upwards of thirty woodcuts interspersed in the text. It 

 is an excellent specimen of German scientific work, the result of 

 nearly five years of uninterrupted labour. It contains not only a 

 description of all the known species of the llhabdocoelidan suborder 

 of Turbellarians, but a full account of the structure of these animals. 

 "Whether it will be followed by a similar volume devoted to the other 

 suborder (Dendroccelida) depends, as Prof. v. Graff states in his 

 preface, upon what Dr. Lang may publish on, or in connexion with, 

 the Turbellarians of the Bay of Naples. 



First in the volume before us wo have a complete bibliography, 

 comprising no fewer than 39G articles. This is followed by an 

 account, filling 137 pages, of the anatomy and physiology, under 

 the heads of the integument, the parenchyma-tissue, the digestive 

 apparatus, the water-vascular system, the nervous system, the sense- 

 organs, and the reproductive apparatus. The geographical distri- 

 bution is then treated of. Then comes the systematic portion of 

 the work, prefaced by a conspectus of the suborders, tribes, families, 

 and genera. Forty genera are defined, and 287 species are described ; 

 but of these some 68 are more or less imperfectly known. Three 

 useful indices close the w r ork. Prof. v. Graff has been fortunate in 

 obtaining aid from many quarters : thus Prof. Semper sent him notes 

 and specimens collected at the Philippines ; Dr. P. Langerhans has 

 furnished him with similar material obtained at Madeira and Tene- 

 riffe ; and the assistance of many other persons is acknowledged. 

 I The Turbellarians form a class or order of small animals with soft 



I bodies, living for the most part in the sea, though a few species have 



been found in fresh water. They are bilaterally symmetrical, des- 

 titute of transverse rings or segments, and without respiratory or 

 circulatory organs. The integument consists of a ciliated epithelium, 

 and contains a continuous muscular snc as well as nettling capsules. 

 They have a mouth, but no vent. With few exceptions they are 

 hermaphrodite ; and some species have the power of multiplying by 

 transverse fission. There are two subclasses or suborders, one of 

 which, the Dendroccelida (not here described), is distinguished by 

 its species having a dendritic or reticulated and branched stomach 

 and fiat more or less leaf-shaped bodies. The female glands are 

 always compact. The Khabdocoelida, the subject of this work, 

 form the other suborder, and are known either by their being desti- 

 tute of a stomach, or by the stomach being when present simple and 

 straight, or sometimes of a lobed shape. The female glands are 





