110 
CIDARIA. By L. B. Pbotjt. 
iruncaia. 
russata. 
albata. 
depuncta. 
jumaia. 
tysfjorden- 
sis. 
cervina. 
perfuscata. 
fuliginosa. 
nigerrimata. 
nigrobran- 
ncata. 
nigroalbata. 
Subgenus Dysstroma Hbn. 
(See Vol. 4, p. 220.) 
Of the Palaearctic members of the very natural “subgenus” (genus) Dysstroma (misprinted Dystroma 
in the German edition) and their Himalayan and other outliers, an excellent monograph has been published 
by Dr. Heydemann in the Mitt. Munchn. Ent. Ges., Vol. 19, p. 207—292, besides some smaller supplementary 
contributions subsequently. His work is of course much too voluminous to be quoted, or even summarized, 
here; but it will have to be taken into account by all future workers at the group. I have adopted the sequence 
proposed by him in the Intern. Ent. Zeitschr., Vol. 26, p. 31, and have found myself in agreement with almost 
all his conclusions, wherever I have been able to check them; for several of the rarer and the most recently 
discovered species, we are greatly indebted to Dr. Wehrli, who lias kindly lent specimens for figuring. Dys¬ 
stroma, is represented by at least 23 Palaearctic or border dine species, several in Northern India, one or two 
each on Formosa, Luzon, Borneo, Sumatra and Java and a score or more in North America. 
C. truncata Hufn. (= centumnotata Schulze) (Vol. 4, pi. 8 k, fig. 2). It has been demonstrated that 
Schulze's centumnotata was virtually the same grey-dusted form from which the species seems to been originally 
described and must therefore be sunk as a synonym. An extremely important paper has just been published 
by Groth (Svendborg), in which he deals with his experiences in breeding truncata ab ovo and their bearing 
on its general biology and heredity (Flora og Fauna 1935, part 3). It has not been possible to rewrite my 
manuscript or even to incorporate all his conclusions, but I have accepted them as regards the rufescens group. 
He has found the species scarcely at all susceptible to immediate environmental factors, and this renders all 
the more secure his deductions as to the Mendelian inheritance; as a result of over 70 breedings ab. ovo, he 
finds it established that the aberrations rufescens , perfuscata and nigerrima (sens, lat.) are dominant over the 
white-banded. — ab. russata (Schiff.?) Him. (= centumnotata auctt., nec Schulze, ? albofasciata L. Mull.) 
(Vol. 4, pi. 8 k, fig. 3, as centumnotata). On account of the sinking of Schulze's form (see above) this name 
has been adopted for the cleaner-banded form which, according to Heydemann, becomes increasingly preval¬ 
ent from Central Germany to dry East Europe. — ab. albata Culot lias the median area broadly white, almost 
or altogether without the dark lines or shades which narrow it in the preceding form. The type was from 
Germany. Probably, however, Dahlstrom's latefasciata (mentioned below) should supplant it. — ab. depuncta 
Romaniszyn is merely diagnosed as being “without the black dots on the venules of the forewings.” The refer¬ 
ence must be to the cell-dot. Described from Mikuliczynie, Poland. — ab. furmata Lange. This name may 
perhaps be used comprehensively for the forms which are intermediate between truncata and ab. perfuscata as 
we have figured them (Vol. 4, pi. 8 k). Heydemann calls it saturata Steph. (which has been sunk as a synonym 
of truncata) and merges in it modesta L. Midi, and griseofasciata L. Mull. — ab. tysfjordensis Strand, which I 
assumed (Vol. 4, p. 222) to be synonymous with citrata ab. simpliciata, lias been transferred to truncata, chiefly 
on account of the almost impossibly early date for a northern citrata (ca. 10—18 July, Tysfjord, Norway, 
68° 10' N. lat., 1 only). Unless it can be proved to represent an aberration of infuscata = schneideri, with 
which its author compares it, it may be applied to the forms of truncata with blackish, somewhat white-mottled 
median band. - ab. cervina L. Mull., a A from Kirschdorf, Upper Austria, end of July is a puzzle. It was 
determined by Heydemam as a specimen of the following (perfuscata) discoloured by age, to which the reply 
is that perfuscata does not occur in the district. The date and the “considerably lighter” hindwing, with the 
submarginal spots “scarcely indicated” suggest a citrata ab., but its author maintains that it is a dusky form 
(suffused with fawn-brown) of the rufescens series. — ab. perfuscata Haw. (= russata part., Hbn.) (Vol. 4, 
pi. 8 k). Although frequent in N. W. Europe, and perhaps the chief form known on Arran, these black-banded 
truncata seem to be wanting from a great part of Eastern Europe and are probably in Switzerland, Austria, 
etc., chiefly confined to the Alps and a few other mountain ranges, thus, as Heydemann opines, conditioned 
bv climate. — Commonly, at least in Britain, the “black” of these forms is duller and more smoky or brownish- 
dusted but has also a strong tendency to suffuse also the distal area of the forewing so as to dull or obliterate 
the ferruginous presubterminal shade. Barrett, who figures it at pi. 356, fig. 1 j, inaccurately calls it saturata 
and Dr. L. Muller has named apparently the same form ab. cervina; but Heydemann has revived for it the 
name ab. fuliginosa (Warr., MS.) Front and this seems to be the oldest legitimate name for it. My suggestion 
(Vol. 4, p. 221) that schneideri Sandb. might be applicable to it, was entirely wide of the mark. Arrar, York¬ 
shire, Nottingham and Wolverhampton are well-known localities for it. — ab. nigerrimata A. Fuchs (= niger¬ 
rima Schawerda, melaina L. Mull.) (11 d). Here the hindwing and underside participate markedly in the dark¬ 
ening, so that the form is definitely melanic. It was described from Elberfeld, a transition (? fuliginosa) from 
Oberursel: rare at (always west of) Kiel, but Heydemann has been successful in breeding it from the egg. 
It is now further known from Denmark, S. Sweden and Yorkshire. — ab. nigrobrunneata Heydem., only yet 
known as a "fa. domestica” was obtained (1 <$, 4 $>$) from a pairing of nigerrimata and would not have been 
named separately but that it shows a character otherwise only known in corussaria: median and terminal areas 
of forewing deep sooty black, basal and antemedian together forming a rust-brown area. — ab. nigroalbata 
Culot is another curious form, grey-brown, with the borders of the median area broadly black, its middle white, 
