182 



Within ray experience this is the rarest of the fusca forms, though 

 widely distribiitecl. I have seen it frora Texas, lS"orth Carolina, Georgia, 

 District of Columbia, Illinois, Colorado, Maryland, New York, Wiscon- 

 sin, Nova Scotia, Lake Superior Region. Mr. Schwarz thinks it more 

 common in the latter region than the other species. In the District of 

 Columbia it is rare, only a few specimens being known in collections. 



I shall not attempt a verbal descrii)tion of the sexual characters of 

 the male, since the figures will give a better idea than could be other- 

 wise given. In the female this species is peculiar by the slenderly fur- 

 cate pubic process, and the triangular upper plates, which are com- 

 pletely separated by the pubic process. The lower plates are quadrate 

 or nearly so. 



L. FUSCA Frohl. 



This is the form which Dr. Horn in his paper suggests as the form 

 probably seen by Frolich, and upon which he based his species. It 



offers no points of superfi- 

 cial difference from the fol- 

 lowing species, with which 

 it agrees in form, color, 

 size, and general habitus. 

 The ventral character in 

 the male must be examined 

 to recognize that sex, and 

 no difticulty will be found 

 in this. The female of this 

 species, on the contrary, 

 differs from all the other 

 forms in that the last seg- 

 ment is not emarginate. 

 This character is at once 

 obvious on examination, 

 and the species is thus 

 readily recognizable in both 

 sexes. 

 A comparison of the fig- 

 ures of the male characters with those of grandis will at once show 

 how they differ, while still after the same general type. The female 

 shows a greater difference, and differs also from all the others of this 

 group by having the pubic process a simple cylindrical rod somewhat 

 dilated medially and terminating in an obtuse point. The upper plates 

 are coalescent on the median line, and are somewhat irregular. 



This species we have from Texas, New York, New Jersey, Ohio, Illi- 

 nois, District of Columbia, Iowa. 



It is the common form around New York City, was the only form 

 found in a large loc of material from Cleveland, Ohio, and was repre- 



Fig. 41.— Lachnosterna fusca. l.clasper of male from front 

 and above ; 2, clasper of male (right) from side; 3, cla.sperof 

 male (leit) from side ; 4, ventral characters of male ; 5, genital 

 structure of female ; 5a, pubic process ; 5&, superior plate.s . 

 5c, inferior plates — enlarged (original). 



