114 Prof. M'lutosh's Notes from the 



5. The Nemerteans in British Text-hooks of Zoology. 



To those familiar with the Sehnurwurmer (Xemertiai) of 

 Gustav von Hayek's ' Hanclbuch der Zoologie ' * in the 

 " seventies," the treatment of the group in most books of 

 zoology intended for instruction and reference in our country, 

 in or bordering on the " nineties," oflfers a subject for comment. 

 Indeed, after a perusal of some recent works (especially certain 

 university practical ones) and their illustrations, the expe- 

 rienced reader arises with a hazy notion as to whether he has 

 not again mentally visited the period when CErsted described 

 the proboscidian sheath as " canalis in quo penis est " and 

 the views of Delia Chiaje, Johnston, Leuckart, Dug^s, De 

 Quatrefages, Huschke, De Blainville, Blanchard, Grube, 

 Gaimard, Kolliker, Williams, J. P. Van Beneden, Max 

 Schultze, Clapar^de, Keferstein, Marion, and others held the 

 field in perplexing variety. Observers so accurate as Kolliker, 

 Frey, and Leuckart, and especially Keferstein, might well 

 marvel, or have marvelled, at the plight of the group in 

 Britain in the year 1898. They would have considered that 

 to the writers of these books English was little known, and 

 that they were unaware of the correct anatomy of the group — 

 in regaid to the structure of the body-wall, the relations of 

 the nerves to the muscular layers, the minute anatomy of the 

 proboscis and its sheath, the digestive and circulatory systems, 

 and other features — as first clearly described (and as it now 

 remains) in their own country. They would be surprised to 

 find illustrations after Max Schultze, who, however, did 

 valuable work on some points, installed as the model from 

 ■which the young anatomist is to learn the general structure. 

 For instance, such figures give expression to the erroneous 

 view that the teiminal ribands of the proboscis are attached 

 to the body-wall. The stylet-region of the organ appears to 

 be composed of disconnected fragments, and, it may be, the 

 tube overrides the commissures of the ganglia instead of going 

 between them, while the circulatory and excretory organs are 

 much behind date. Other figures carry the proboscis-sheath 

 forward to the tip of the snout, though it is not clearly 

 explained how the proboscis is to hang on to its owner. 

 Another, by a bolder flight, even makes the aperture for the 

 proboscis the mouth. In displaying the structure of this 

 remarkable organ (quite unnecessarily called " introvert " or, 

 it may be, " the hollow eversible anterior end of the animal ") 

 nature is eschewed, and by a series of mechanical diagrams, 



* AVien, 18"". 



