284 
Hermaphroditism etc\ in Pediculus 
thorax. In the $, the corresponding muscles occur dorsally only in the last 
three segments; ventrally in two of the middle segments and anteriorly, 
adjoining the thorax, the series in other words being interrupted (in corjporis) 
by the absence of such muscles in one segment. 
I. 
HERMAPHRODITISM IN PEDICULUS HU MAN US. 
Previous observations. The only reference in the literature to the occurrence 
of hermaphroditism in lice is that contained in a brief passage of a preliminary 
note of Sikora’s (v. 1917, p. 173). This author states 1 that she observed 
hermaphrodites among “wild” lice and others raised in captivity. The 
abnormal individuals varied in structure. On the one hand what appeared 
to be an otherwise normal male would possess an abnormal “gonopodial 
spot and rudimentary vulval folds,” on the other hand a female would exhibit 
abnormally pigmented tergites which afforded the only external sign of the 
bi-sexual structure of the internal genital organs, this condition being accom¬ 
panied by abnormalities affecting (a) almost invariably the structure of the 
thumb of leg-pair I and (6) occasionally the abdominal musculature. Sikora, 
having collected 70 abnormal specimens of the kind, proposed to make them 
the subject of special study. We are not aware, however, of her having 
published any further particulars on the subject. 
Method of examination. 
As all the material here described had been preserved in alcohol, we 
employed the simple method of examining the specimens when impregnated 
with cedarwood oil. This was of advantage since it rendered it possible to 
study the internal organs in situ without their being displaced, and facilitated 
the discovery of the invaginated structures that would otherwise have been 
invisible from the outside. 
Whilst a number of the foreign specimens grouped under (6) in the sub¬ 
joined list had the internal organs macerated, a few of them were sufficiently 
well preserved to permit of their internal structures being studied. In a few 
cases attempts were made at dissection but only with moderate success. 
1 Sikora writes: “Ich mochte auch noch erwahnen, dass ich sowohl unter den wilden als 
auch unter den in Gefangenschaft aufgezogenen Lausen Hermaphroditen fand, vom anscheinend 
normalen mit einem Gonopodenfleck und rudimentaren Vulvaklappen bis zum $, an dem 
nur Pigmentierung der Tergite ausserlich den zwitterigen Bau der Keimdriisen verrat, der fast 
immer von Abnormitaten am Daumen des ersten Beinpaares und zuweilen auch der Abdominal- 
muskulatur begleitet ist. Teh werde das zahlreiche Hermaphroditenmaterial (etwa 70 Stiick) 
systematisch bearbeiten.” 
By way of comment it may be noted that unpigmented “tergites” (our dorsal bands) are 
not present in females as Sikora would seem to imply. We are here dealing with a structural 
character in relation to which pigmentation has no significance since it may or may not be in 
abeyance whilst the structure persists. 
