198 Natural History of Entozoa. 



the young from the egg, they may get into the bodies of 

 certain insect larvae, or even of small land mollusks ; but he 

 11 thinks it more likely that they either enter the substance of 

 vegetable matters, or bury themselves in the soil at a short 

 distance from the surface." Salt, a weak infusion of tobacco, 

 or turpentine will kill these worms, and they may be extracted, 

 by means of a feather, from the throat. 



In the preceding observations we have made free use of 

 Dr. Cobbold's book, which demands a special notice at our 

 hands. It is a splendid volume. Indeed, very few scientific 

 works will compete with it for elaborate and beautiful illustra- 

 tion. This is a feature of great importance, as the entozoa 

 can not be studied with any sort of convenience except with 

 the aid of thoroughly well-executed drawings. Considerable 

 knowledge and skill is required to prepare them so as to make 

 them reveal their structure, and it is only from such exquisitely- 

 made portraits as those of Dr. Cobbold that ordinary students 

 can understand the peculiarities of their organization. Dr. 

 Cobbold has worked at this difficult branch of natural history 

 with exemplary patience and perseverance. He has added an 

 important store of facts from his own observations, and has 

 familiarized himself with the voluminous and scattered literature 

 of the subject. The plan of his volume is first to give a 

 sketch of the subject, with a description of the principal kinds 

 of entozoa. Then follows a division especially devoted to the 

 parasitic worms affecting man, and lastly we have a section 

 entitled " Spurious Helminthology," in which a variety of 

 important information is given concerning creatures that are 

 not true Helminths, but which have been found, or repre- 

 sented, as parasitic in the human frame. The readers of the 

 Intellectual Observer are familiar with Dr. Cobbold's skill 

 as a draftsman, and they will readily appreciate the value of 

 twenty-one coloured and tinted plates, comprising a hundred 

 and fifty-six separate figures, to which are added eighty-two 

 woodcuts. The mode of dividing the subject adopted by 

 Dr. Cobbold, appears to have had special reference to the 

 convenience of medical men, whose attention to the subject is 

 indispensable, and who can in no other publication obtain such 

 complete information concerning the character of the parasites, 

 the evils they cause, and both the preventive and the remedial 

 means that it is most desirable to adopt. 



There is still a great deal to be searched out in the natural 

 history of the entozoa, and it will prove a great advantage to 

 English students to have in their own language a work 

 executed with so much care, and bringing to a focus an amount 

 of scattered information that requires a knowledge of many 

 languages, and the labour of many years to collect. 



