310 ANNUAL RECORD OF SCIENCE AND INDUSTRY. 



ginia, has been discovered by Dr. Packard on the shores of 

 the Great Salt Lake. The different species of animals (a 

 helix, myriopod, harvestman, and poduran) inhabiting the 

 cave are described in Hay den's Bulletin. 



Professor C. V. Riley's ninth report on the injurious insects 

 of Missouri contains new and fresh information regarding the 

 Western locust, the Colorado potato beetle, with maps illus- 

 trating their extension East. Other injurious insects are 

 more or less fully treated. 



A work of a very high degree of interest to philosophic 

 naturalists is Professor Weismann's " Studies on the Theory 

 of Descent" ("Studien zur Descendenz-Theorie"), of which the 

 second part has just appeared. It is divided into four sec- 

 tions, with the following subjects : "The Origin of the Mark- 

 ings of Caterpillars;" "On the Phyletic Parallelism in Meta- 

 morphic Species ;" " On the Transformation of the Mexican 

 Axolotl into an Amblystoma;" "On the 3Iechanical Concep- 

 tion of Nature." In the last chapter, which will interest 

 thinkers, the author, while stating his belief that evolution 

 lias been accomplished mechanically, claims that this view 

 of nature neither leads to materialism nor excludes teleol- 

 ogy- 



In a recent essay on the origin of insects, Dr. Mayer, of 



Jena, suggests that the ancestor of the insects was winged. 

 This view is opposed by Dr. Packard, who publishes a re- 

 view of Mayer's essay in the American Naturalist for No- 

 vember, in which he maintains, with other writers on this 

 subject, that they must have originated from larval forms, 

 and claims priority for certain conclusions proposed as novel 

 by Dr. Mayer. 



In a recent work on the morphology of the tracheal or 

 respiratory system of insects, Dr. J. A. Palmen arrives at the 

 conclusion that the primitive number of pairs of spiracles, or 

 breathing-holes, in insects is eleven, thus agreeing with the 

 views previously expressed by Packard in a brief essay pub- 

 lished on the same subject in 1873. Palmen's work comprises 

 one hundred and fifty pages, and is quite exhaustive. He be- 

 lieves that the tracheal system was at first, in its primitive 

 form, open i. c, consisting of a series of tubes connecting by 

 spiracles or holes with the outer world. In certain aquatic 

 insects the system became closed, the larva breathing by ex- 



