80 REPORTS OF INVESTIGATIONS AND PROJECTS. 



laboratory are very rare. The inheritance is AlendeHan, H. quinqnesignata, 

 the darker form, being dominant. This makes it desirable to consider H. 

 lecontei a variety of H. quinqnesignata. The attempt to cross typical speci- 

 mens of H. lecontei with H. convergens has always met with failure, except 

 with one pair, where a very small percentage of the eggs developed. How- 

 ever, an abundance of fertile eggs are obtained in crossing H. convergens 

 with specimens of H. lecontei having some deficiency of pigment, in that 

 respect approaching the much lighter H. convergens. Apparently the true 

 gap between H. convergens and lecontei is a physiological one. Judging by 

 pattern alone, some individuals, really extremes of H. convergens approach- 

 ing H. lecontei, may be wrongly taken to be H. lecontei. Breeding alone 

 can discover the true condition. This throws light on the distribution of 

 H. glacialis, which species has a pattern differentiated by certain losses and 

 coalescences from its closest ally, //. convergens, with which, however, it is 

 intersterile. It is found commonly only in the northeastern United States and 

 northward. Yet, in large series, one sometimes finds specimens that technic- 

 ally comply with the description of H. glacialis, but which are far too rare 

 to be able to find mates and maintain their existence. Breeding tests convince 

 me that those are really in the H. convergens intergenerating unit, and that 

 to regard them as H. glacialis upsets any true conception of the geographical 

 distribution of that species. Such a conclusion is of course unfortunate for 

 the taxonomist, but I see no escape. 



A series of species and varieties of another section of the genus Hippo- 

 damia have been described from the Western States, characterized by a black 

 line along the sutural margin of the wing-cover and various degrees of longi- 

 tudinal coalescence of spots. Another series has the corresponding degrees 

 of longitudinal coalescence of spots, but lack the long black line along the 

 suture. One would naturally, in projecting the phylogeny of these beetles, 

 arrange them in two parallel lines in the order of degree of coalescence; 

 but in taking females from nature the progeny show us that the black line 

 along the suture is a unit-character not preventing the common intercrossing 

 of these two series. The phylogeny must be construed, therefore, as taking 

 place in an interlacing manner rather than in two parallel lines. 



Adalia frigida is found in a number of varieties, several of them often in 

 association. Females of one variety from nature have in my experiments 

 given under the same conditions four of these varieties. From a network 

 of coalescent spots to spotlessness there is a series of steps, or, to use Galton's 

 illuminating expression, ''positions of organic stability," into one of which 

 these beetles develop in spite of intercrossing and the non-utility of the 

 pattern. In Europe and parts of this country, where A. bipunctata has been 

 introduced, one occasionally finds Adalias which have the pigment very much 

 extended, but leaving some of the reddish ground-color in a characteristic 

 pattern. This interbreeds with A. bipunctata and yet holds its entity by 

 alternative inheritance. I have found this same pattern in eastern Wash- 

 ington with our native Adalia and far from any A. bipunctata. This, with 

 other records, shows that it has arisen independently from this species. An 

 independent appearance in two species of the "extensa mark" referred to 

 below, of longitudinal fusions, transverse fusions, and spotlessness in several 

 genera or species in this family points strongly to the determinate nature of 

 the mutations or variations, such as we have in orthogenesis. From the 

 evidence found, polyphyletic origins of varieties and species must be far 

 more common than generally supposed. 



