loS 



CURRENT LITERATURE. 



Nierstrasz, H. F. — The Solenogastres of the Siboga-Expedition. Siboga- 

 Expeditie. Monog. xlvii. Leyden : 1902. pp. 46, pits. i-vi. 



One of the most important memoirs of recent years, upon the structure and 

 classification of the Solenogastres, is that just published in connection with the 

 "Siboga" Expedition. 



Hitherto only two species were known from the East Indian Archipelago 

 viz. those described by Thielc in iSgS—Xofotiieuia clnvigcra and Proneomeiiia 

 aiistralis. The 'Siboga' expedition has been extremely fortunate, bringing back 

 no less than 65 specimens, which are contained in 8 genera, of which 4 — 

 Diiioiiiciiia, Proparauieiiia, Heniiinenin, and Cydoincnia — are new. .A.I1 the 

 species, twelve in number, are also new. 



The geniH Duunicnia is ch ir icterised by the presence of a thick cuticle, in 

 which are many layers above each other of hollow, pointed spicula. The 

 papillae are numerous. There is a dorso-terminal sense organ present, three 

 ventral folds ; two separate, unramified, tubular salivary glands ; and cloacal 

 ducts with vesicular appendages. There are no gills and the radula is distichous. 

 Two sptcies are described, D. hnlnxchti^ and D. verrucosa. The genus is 

 regarded as related to Proncoincnia because of the integument, and to 

 Paramenia on account of the distichous radula. 



The genus Proparanienia has also a th'ck cuticle with many layers of pointed 

 spicuh, and numerous papillae. There is no dorsal sense organ, and no copulation 

 spicula. There are 3 ventral fold ; 2 separate, ramified salivary gland ; 2 vesicular 

 receptacula seminis ; and a circlet of gills in the cloaca. The radula is monoserial. 



Heinimenia while closely related ioXeomenia, differs from it in the structure 

 of the integument, which has a thin cuticle, with flat imbricated spicula, and no 

 papillae. It is very rightly regarded as a transition form, and as such may be 

 compared with Paramenia, Pruvot. 



Clyclomenia is another similar genus, exhibiting relationship to Proparamenia 

 on the one hand and Paramenia on the other. 



The author divides the Xeomeniidac into two groups, viz.: A. Those forms 

 possessing a thick cuticle, with numerous pointed, hollow spicula in different 

 layers, and a large number of hypodermal papillae, and B. Those forms with a 

 thin cuticle, covered with a layer of flat, imbricated spicula, and no hypodermal 

 papillae. He further points out, that taking the radula as a basis ol classification, 

 we have the family divided into three groups, viz. a. Forms with polystichous 

 radula, b. Forms with distichous radula, and c. Foims without a radula. It 

 further appears that there is a correspondence between groups A and a, and 

 groups B and b, with certain exceptions such as Dondersia and Macellomenia. 



If we might suggest a slight improvement upon this, it would be as follows: 

 Group i.— Neomeniatina for group .\ of Nierstrasz. 

 ii. — Parameniatina for intermediate I'orms. 

 iii.— Metameniatina for group B of Nierstrasz. 



The author then discusses in some detail the relationships of the known 

 genera of Neomeniidac, which are summarised in diagrammatic form. 



In additions to the conclusions stated above. Dr. Nierstrasz has set forth in 

 great detail, with a wealth of illustration, a host of anatomical facts on the 

 structure of the new genera and species, which in the present state of our 



