314 
Im vollkommen ausgestreckten Zustande hat es die in vorstehen- 
der Figur dargestellte Form. 
Ich entdeckte diese neue Art vor drei Wochen in einem Tümpel 
in der Umgebung von Krakau. Sie scheint hier sehr selten zu sein, 
wenigstens ist mir bisher nicht gelungen zahlreichere Exemplare 
zu erbeuten. 
Näheres über den Bau und die Entwicklung dieser Art werde ich 
in Kurzem an anderer Stelle berichten. 
Krakau, den 6. Juni 1893. 
3. The »Head« of Galeodes, and the Procephalic Lobes of Arachnidan 
Embryos. 
By Henry M. Bernard, M.A., Cantab. 
(From the Huxley Research Laboratory, South Kensington.) 
eingeg. 10. Juni 1893. 
Considerable mystery surrounds the very striking »procephalic 
lobes« of Arachnidan embryos, and attempts have been made to see in 
them a number of vanished segments. A simpler explanation, however, 
lies near at hand. 
As is well known, a distinct head has been claimed for Galeodes, 
a character which is supposed to distinguish it from all other Arach- 
nids. No true head really exists; the appearance of a head is due to 
the peculiar shifting backward of parts of the last (cheliceral) segment 
dorsally over those immediately following it. 
On opening up this so-called head of Galeodes, it is found to con- 
sist of two hollow lobes of chitin fused together in the middle line, 
and posteriorly to the terga of the following segments. These lobes 
are entirely filled up with muscle for moving the chelicerae. Further, 
the cheliceral muscles are confined to these lobes, and none but che- 
liceral muscles run into them. 
The origin of these cephalic lobes in Galeodes is not difficult 
to see. The development of the first pair of limbs as powerful seizing 
organs which were at first thrown forward on each side of the mouth, 
and eventually met in the middle line above the prostomium, necessi- 
tated an upward and backward development of the lateral parts of the 
segment for the attachment of the muscles of these appendages. The 
first segment is thus greatly distorted; its lateral parts have developed 
as two great shoulders for the carrying of the mandibles, and these 
shoulders have fused in the dorsal middle line to form a new dorsal 
surface across the anterior region of the cephalothorax. A compa- 
rison of the diagrams will make my meaning clear. 
