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One of the reasons why I submitted this „law“ to a fresh test was that a number
of the proofs given by Gr. H. Fowler seemed to be altogether too good.
As is seen from the account given above, out of all the Halocyprids of which
two or three stages had been found by G. H. Fowler all except three, Conehoecia magna,
C. loricata and C. ametra, agreed very well with ßROOKS’s law.
In the case of C. magna G. H. FOWLER tried, as will be seen above, to explain this
deviation by assuming that the material investigated was not pure. This explanation is
certainly correct. Stage I (= Conehoecia macrocheira G. W. MÜLLER) and Stage II (= C. magna
C. CLAUS) are (as is pointed out in the special part of the present treatise) certainly two
quite distinet species.
In the case of the two other of these three species the cause of the deviation is to be sought,
according to the same author, in the small number of individuals that were investigated.
Whether this explanation is correct for C. ametra I must leave undecided; it is to be noted that
the growth-factors obtained from the average lengths that were actuallv observed vary a good
deal; cf. above. With regard to C. loricata it ought to be pointed out that the material
investigated was presumably impure. Stage I ( Conehoecia ctenophora G. W. MÜLLER) and
Stage II (= C. loricata [C. Claus]) are presumably to be regarded as two closely related species;
cf. the special part below.
All the other of these species agreed very well with BROOKS’s law, as has been
mentioned above; these species were: Halocypris globosa, Conehoecia spinifera, C. elegans,
C. procera, C. rotundata, C. curta, C. Haddoni, C. hyalophyllum, C. rhynchena, C. imbricata
and C. daphnoides.
In spite of this agreement it is probable that the material of so me
of these species was not pure. Thus in the case of Conehoecia curta Stage I
(= C. stigmatica G. W. MULLER) and Stage II (= C. curta J. Lubbock) certainly represent
two well differentiated forms. The same is true of Stage I and Stage II of C. hyalophyllum-,
Stage I = C. lophura G. AV. MÜLLER, Stage 11 — C. hyalophyllum C. CLAUS. Nor is it impossible
that a mixture has also taken place in the case of the larvae of C. rhynchena, as this writer points
out on p. 248 that , ,it is probable that C. Jcampta or C. tyloda may be the oldest stage of this
species“. It seems to be beyond all doubt that C. kampta G. W. MÜLLER and C. tyloda
G. W. MÜLLER are forms that are well differentiated both from each other and from C. rhynchena.
Both these species occur in the material investigated by G. H. FOWLER — according to this
author — only as mature individuals. Were there also larvae of these two species among the
larvae of C. rhynchena? For the reasons why C. stigmatica, C. curta, C. lophura, C. hyalophyllum,
C. rhynchena, C. kampta and C. tyloda represent different forms I s hall only refer here to what
is w ritten in the special part of this work.
For Stage 1 and Stage II of C. rotundata the reader is referred to what is written about
this species in the special part of this work. The result of G. H. FoWLER’s investigation of
C. daphnoides and Halocypris globosa seems also to merit further vérification. The length of
the first stage of C. daphnoides varied from 2,6 -3,5 mm; only a single specimen of Stage III
wTas found and yet the law agreed perfectly!
A criticism of G. //.
Fou’ler’s exposition.
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