1148 
And on p. 69: “Interesting features are shown by the Sciomyzidae. 
Many of their species show colourseams of the transverse veins; 
pigmentation of the longitudinal veins is found in Tetanocera elata, 
Elgiva lineata, of the anterior margin in T. elata. Marked punctuation 
occurs in numerous forms, e.g. T. punctata; the points usually 
being arranged in one row in the hindmarginal cell, in two rows 
in the remaining cells. These rows lie along the side of the nervures, 
or in other words, each nervure lies between two rows of spots: 
the spots to either side often corresponding to each other, though 
not always; also the spots placed along the two borders of the 
same cell frequently form pairs. On page 58 [argued that I consider 
these two lateral rows of spots as derived from the division of one 
median row. In T. punctata an accessory median bar is only 
slightly developed, but in other species this bar and the lateral 
spots are intimately connected; coryleti and unguicornis already 
show this connection more clearly than punctata and marginata, 
fumigata ete.; it leads to preponderance of the dark colour, only 
two rows of hyaline spots being left free. In punctulata and 
umbrarum the scheme of the colour pattern is still further differen- 
tiated by the more specialised character of the spots in certain 
transverse bands.” 
“Among Sciomyzines Se. albocostata, cinerella, fumipennis show 
a marked striation of the longitudinal veins, leading in the last 
named species to almost complete vanishing of the ground colour. 
Spots on the transverse veins.are found in griseola amongst others, 
transverse bars are developed in bifasciella, a median row of spots 
in the hind marginal cell is characteristic of Schönherri. By bipar- 
tition of these spots I should be inclined to explain amongst others 
the condition of Tetanocera punctata, possessing double rows of spots. 
The same degree of differentiation has been reached by Sciomyza 
javana, which in Se. albocostata is accompanied by a white disco- 
loration of the margins. In this family also therefore, we see several 
different motives of markings among nearly related forms.” 
De Mrijerr therefore, though acknowledging the fundamental equi- 
valency of dark spots on a light ground and light spots on a dark 
one, does not arrive at the conclusion which I have drawn from the 
presence of a median bar; on the contrary he considers the two 
paramedian rows of spots in a cell as derivatives of one median 
row. A case like Poecilostola, where in one single cell a median 
row occurs between two lateral ones, and it is exactly this cell 
which belongs to those internervural spaces that may be supposed 
to have originated by the coalescence of two neighbouring cells 
