i8 9 6. SOME NEW BOOKS. 343 



width. To form the subject of the last chapter, a glossary of osteolo- 

 gical terms has been thrown in, apparently as an afterthought, for 

 it is not specially related to the subject of the book. The derivation, 

 or rather the author's idea of the derivation, is given for most of the 

 words, and here the classical scholar may gather much information 

 of which he was erstwhile ignorant. He may learn, for instance, that 

 zugnum means " I yoke together " ; trochas, " I roll or run round " ; and 

 pJiusis, "I grow"; while, if his predilections lie in the direction of 

 Latin, he may learn the meanings of a great many words which do 

 not occur in the dictionary. The author has evidently been unable 

 to decide whether to render the Greek letter " upsilon " by u or y, and 

 so gives us an equal quantity of both. This, of course, has the 

 advantage of relieving the monotony of an otherwise unattractive 

 glossary, and further variety is afforded by deriving "pterygoid " from 

 pteron, and " basipterygoid " from ptevygion, although the roots of 

 " entopterygoid " and " mesopterygoid " are recorded as pteryx and 

 pternx respectively. It is also not encouraging to the inquiring 

 student to be told that the supratemporal is " a bone of the skull in 

 certain Vertebrata," more especially as splenial, prefrontal, and 

 ectopterygoid are described in exactly the same terms. 



In spite of these deficiencies which the carping critic sets himself 

 so assiduously to ferret out, there is abundant evidence of the patience 

 and perseverance which the author has exercised in his endeavour to 

 produce a concise and reliable students' manual. We cannot say 

 that this endeavour has been crowned with unqualified success, and 

 it is to be feared that the author will not greatly benefit by the publi- 

 cation of the work. There was no demand for the book, and the 

 thirty closely-printed and well illustrated pages devoted to the skull 

 of the dog in Flower's " Osteology of the Mammalia," to which 

 students have had recourse in the past, still remain far and away 

 the best source of information on the subject. 



W. R. 



Plankton Gastropods. 



Die Gastropoden der Plankton-Expedition. Ergebnisse der in dem Atlan- 

 tischen Ocean von Mitte Juli bis Anfang November, 1889, ausgefiihrten 

 Plankton-Expedition der Humboldtstiftung. Von Dr. Heinrich Simroth. 

 Pp. 206, twenty-two plates, seventeen cuts. Kiel und Leipzig, 1895. 



The Gastropoda collected during Professor Hensen's Expedition in 

 the "National " were confided for examination to Dr. Heinrich Simroth, 

 who, as might have been expected, found his investigations beset with 

 no ordinary difficulties, owing partly to the small size of the organisms 

 and the distorting effect of reagents upon them. Comparatively few 

 of them could be named, as in the present state of our knowledge it is 

 impossible to refer them with certainty to particular adults. 



The first section of this report is devoted to the genus lantkina, 

 and numerous features in its structure and life-history are discussed. 

 The radula is divided quite to the base into two halves, and the sides 

 of the mouth are supported by lamelliform jaws. The teeth appear 

 to serve as a sieve for straining the minute plankton on which the 

 animal feeds. The float consists of different elements ; the propodium 

 supplies a homogeneous mucus, of which the air-bubbles are formed ; 

 the mesopodium a thread-like byssus; there is, further, a colour gland 

 to which the varying tint of the float is due. The eggs (to the number 

 of 4,000 in /. nmbilicata, 400,000 in the larger species) are deposited on 

 the under surface of the float by a protrusible ovipositor, and the 

 process takes place all at once. Where a float shows traces of two 



