186 SUMMARY OF CURRENT RESEARCHES RELATING TO 



on the ground that the thoracic legs of Uronectes are destitute of exo- 

 pods, but Caiman doubts the statement that the absence of these has 

 been definitely proved, and regards the discovery of stalked eyes, both 

 in Gasocaris and in Uronectes as confirmation of his view. He thinks 

 that exopods were in all probability absent in the former of these two 

 genera, but were present in Uronectes. But he points out that as his 

 original contention was that Gasocaris and Uronectes are related to 

 Anaspides — a doubtful Schizopod — the presence or absence of exopods 

 does not in any way affect the question. 



Annelida. 



Life of Earthworms. * — Dr. K. Bretscher communicates some care- 

 ful bionomical observations on earthworms. (1) There are normal 

 wanderings, at all seasons and at all ages, prompted by nutritive and 

 reproductive needs. (2) All the local species (Zurich), both large and 

 small, whether young or old, burrow deeply ; there are no forms which 

 can be described as restricted to the humus ; and there is no particular 

 relation between form of body (flat or cylindrical) and the burrowing 

 power. (3) The process of pairing, in spite of the numerous observa- 

 tions which the author partly corroborates and partly criticises, remains 

 in various respects obscure. 



Hirudo troctina John.f — Marcelo Bivas Mateos gives a diagnosis 

 of this leech, common in some parts of Spain. He notes its variability, 

 but maintains its specific distinctness. 



Notes on iEolosoma tenebrarum. X — V. Janda refers to Miss Brace's 

 work § on this worm, and points out that it is in great part a corrobora- 

 tion of what he had previously described || in regard to the nervous 

 system and musculature. The authoress has also overlooked the work 

 of P. J. Schmidt on the same subject. 



Geographical Distribution of Priapulus.f — A. S. Skorikow has 

 several notes on this subject, but his most interesting statement is that 

 Pr. caudatus var. avtarcticus, which was formerly regarded as wholly 

 antarctic, is really bipolar. It has a circumpolar Arctic distribution, 

 and it seems to be widely distributed in the south. 



Platyhelminthes. 



Platyhelmia, Mesozoa, and Nemertini. ** — Prof. W. Blaxland 

 Benham discusses these in the fourth part of the ' Treatise on Zoology,' 

 edited by Prof. E. Bay Lankester. His careful and detailed treatment 

 of forms which are so often passed over summarily in zoological text- 

 books is very welcome, and will form a valuable work of reference for 

 those interested in Turbellarians, Trematodes, Cestodes, Nemertini, and 

 the heterogeneous Mesozoa. 



J n^ 



* Biol. Centralbl., xxi. (1001) pp. 538-50 (3 figs.). 



t Boll. Soc. Espan. Hist. Nat., i. No. 10 (1901) pp. 375-7 (1 fig.). 



j Zool. Anzeig., xxv. (1902) pp. 172-4. 



§ Journ. Morphol., xviii. (1901). || SB. k. bohm. Ges. Wiss., 1900. 



f Zool. Anzeig., xxv. (1902) pp. 155-7 (1 fig.). 



• * A Treatise on Zoology. Edited by E. Bay Lankester. Part iv. ' The Platy- 

 helmia, Mesozoa, and Nemertini,' by Prof. W. Blaxland Benham, London. 1902, 

 3vo, iv. and 204 pp. and many figs.). 



