272 NATURAL SCIENCE. April, 



abroad is given, but so far as Ireland is concerned this information is 

 not altogether trustworthy. 



In 1891, Dr. Standfuss published a small " Handbuch fur Sammler 

 der europaischen Gross-Schmetterlinge." The work now sent us is an 

 enlarged second edition, but with so much valuable matter added as 

 to make it practically a new book. 



The first section of the work deals with the collection of lepidoptera 

 in all stages ; the student is told how, when, and where to find and 

 capture eggs, caterpillars, pupae, and moths. The second section, 

 which occupies by far the greater part of the book, is devoted to the 

 breeding of lepidoptera from both the practical and the theoretical point 

 of view. One of the leading features of this division is the part 

 dealing with crossing and hybrids. A valuable summary is given of 

 the recorded instances of pairing between insects of different species, 

 with notes as to whether any progeny resulted. The author remarks 

 that the hybrid obtained by the crossing of two species differs from 

 the progeny of the same two species if the sexes be reversed. Several 

 of the figures in the very excellent coloured plates illustrate results 

 obtained by the author in a series of experimental crossings with three 

 species of Saturnia. Specially interesting are two successful crossings 

 of a male hybrid with the female of one of its parent species. The 

 comparative ease with which these moths interbreed and the fertility 

 of some of their hybrid offspring suggest that the species have not 

 long been separated from each other. From a comparison of the larval 

 and imaginal characters of the three, Dr. Standfuss concludes that 

 S. spirit is the oldest form and that 5. pavonia (the only one we have 

 in these islands) is older than S. pyvi. 



Detailed directions are given about the rearing of caterpillars, 

 and warnings as to the various sicknesses to which they are subject. 

 An interesting statistical table shows the relative numbers of the two 

 sexes bred in forty species of butterflies and moths of various families. 

 In every case the males preponderate, the average being nearly 107 

 males to 100 females. The variation of colour and markings in the 

 Lepidoptera is discussed at some length, and British entomologists will 

 be interested to see references to some of the melanic forms which are 

 so prominent a feature in our own moth-fauna. Dr. Standfuss points 

 out that the Shetland males of Hepialus humuli (var. hethlandica) must 

 represent the ancestral form of the species — the ordinary white male 

 of this moth being evidently a newer development. He therefore 

 oddly suggests that H. hethlandica, Knaggs, should stand as the specific 

 name, H. humuli, L., being relegated to varietal rank. Similarly, he 

 holds that the var, rustica of Spilosoma mendicum, in which the male is white 

 instead of black, represents the ancestral form of that species ; while 

 some experiments in crossing the type with the variety show 

 that the latter has the stronger influence on the progeny. It is 

 remarkable that the var. rustica should almost entirely replace the 

 typical S. mendicum in Ireland, while on the continent it is a south- 

 eastern form, being recorded from Hungary, Roumania, Asia Minor, 

 and Armenia. 



A list of species which exhibit seasonal dimorphism is given, with 

 some account of the experiments which Weismann and others have 

 made to elucidate the question. A very complete summary of 

 experiments by the author and others on the influence of heat or 

 cold on the markings of butterflies of the genus Vanessa and allies is 

 perhaps the most valuable feature in the whole book. Concluding 

 that the more a species is affected by such experiments the more 

 newly developed it must be, Dr. Standfuss arrives at a phylogeny of 



