36 THE NAUTILUS. 



looks very much like C. integrum. Possibly that species should have 

 been included in the Chicago fauna. 



The paper concludes with a full bibliography of the literature of 

 the Area, and a list of all the works referred to, which in itself will be 

 of valuable assistance to the student who desires to familiarize him- 

 self with the literature, especially that published since Binney's 

 Bibliography was issued. BRYANT WALKER. 



ENTEROXENOS OSTERGRENI, A NEW ENDO-PARASITIC GASTRO- 

 POD. In the current number of the Zoologische Jahrbiicher (xv, 

 pi. 4, p. 731) a new parasitic gastropod of unusual interest is 

 described by Kristine Bonnevie. It lives in the body-cavity of the 

 N. European holothurian Stichopus tremulus, usually near the 

 anterior end of the intestine, to which it is attached. The adult 

 animal is vermiform, 6-15 cm. long, 4-5 mm. in diameter, without 

 visible external opening, suddenly contracted anteriorly, into a 

 slender style which is run into, and attaches it to the intestine of the 

 host. The largest individuals sometimes lie free in the body-cavity. 

 The integument is smooth, white and opaque. Under the epithelium 

 there are circular and longitudinal layers of muscle. The internal 

 anatomy is very simple. There is a narrow, long, central cavity, 

 running backward from the end of the peduncle of attachment, the 

 large ovary opening into it distally, while the testis lies anterior. 

 The eggs are fertilized in the central cavity of the animal, and 

 undergo development there. No trace of an alimentary canal is 

 present. The gastropodous nature of the parasite is shown by the 

 development and embryo. 



The relationships of Enteroxenos are apparently with Entocolax 

 and Entoconcha, but it is a more advanced evolution-product. The 

 author gives provisional and guarded adherence to Schmiemenz's 

 theory of the mode of derivation of Enloconcha from Stylifer-\\ke 

 ectoparasites, but wisely abstains from homologizing the parts of the 

 endoparasitic forms with those of normal mollusks, preferring to 

 leave open the questions of the homologies of the body-wall, style of 

 attachment and central cavity. H. A. P. 



A REVISED CENSUS OF THE MARINE MOLLUSCA OF TASMANIA. 

 By Prof. Ralph Tate and W. L. May. (Proc. Linnean Soc., New 

 South Wales, pp. 344-471. Issued Dec. 19, 1901.) 



This valuable contribution consists of an introduction to and history 

 of marine conchology in Tasmania; a systematic list of species ; a 

 catalogue of synonyms with the corresponding names adopted ; criti- 

 cal remarks on some species, and descriptions of two new species and 

 one new genus (Legrandina). The work is illustrated by five 

 plates, containing 107 figures and 14 figures in text. A summary of 

 admitted species shows : 10 Cephalopoda, 504 Gastropoda, 4 Scapho- 

 poda and 157 Pelecypoda, a total of 653 species. It is a truly up- 

 to-date catalogue, very few of the more recent improvements in 

 nomenclature being overlooked. C. W. J. 



