REVIEWS — DR. LANKESTEr's LECTURES. 361 



digestion as a Highlander, Iresh from his mountain wilds, is known to 

 possess." — May we ask, by the way, how it is that our familiar friend 

 Solen siliqiui appears here under the specific name of maxirnus, a name 

 which we do not even recollect as a synouyme ? It is true we have 

 not at hand good references on British conchology, but we cannot 

 help suspecting that our author, writing from memory, used a wrong 

 name. It would be useless for us to protest against the zoological 

 system which our author, in common with, ^perhaps, the leading Euro- 

 pean zoologists at the present time, has adopted. It is enough for 

 us to repeat, that we hold firmly to the divisions Articulata and Radi- 

 ata instead of Annulata and Coelenterata ; but we should have expec- 

 ted from Dr. Lankester, according to the system he has employed, 

 that he would have better appreciated the value of the sub-kingdoms 

 than to have spoken, as he has often done, of Vertebrata and Inver- 

 tebrata in contrast. We had understood it to be agreed upon among 

 philosophical zoologists, that invertebrate animals cannot now be 

 regarded as in any sense a division, and that the distinctions between 

 Mollusca, for example, and either of the other sub-kingdoms, are 

 quite as important as those which separate them from Vertebrata. 



Dr, Lankester's other volume occupies ground at least as interesting 

 and important as that of which we have spoken ; and he has treated 

 his subject with the same knowledege, care and judgment which are 

 manifested in it. His object is to give useful information by explain- 

 ing the relations of food in its several kinds to the support of the 

 system, and to the health and enjoyment of human beings. We fear 

 he may have assumed a more general acquaintance with the elements 

 of chemistry than his readers will possess ; but he will, no doubt, 

 succeed by the clearness of his explanations in making most readers 

 sufficiently comprehend his meaning. He divides human food into 

 three classes: 1. Alimentary or necessary food; 2. Medicinal or 

 auxiliary food ; 3. iVccessory food. The latter kind, of which gum 

 and gelatine are examples — not contributing anything to the support 

 of the frame, but being merely a useful accompaniment to things that 

 do. The first class contains three groups: I. Mineral — as water, 

 salt, and various substances found in the ashes of plants and animals ; 



2. Carbonaceous or heat-giving, to which belong starch, sugar, fat ; 



3. Nitrogenous or flesh-forming, consisting of albumen, fibrine, 

 caseine. The second class has likewise three groups — the 4th consist- 

 ing of stimulants, as alcohol and volatile oils ; the 5th of neurotics 



Vol. VII. V 



