REGENERATION OF ANTENNZ—SCHMIT-JENSEN. 527 
matter of course these species should be chosen for these experi- 
ments in which the tendency to homeosis is found in nature. 
In the ‘‘Zoologischer Jahresbericht,” from 1891 to 1911, I have 
found the following records of homceosis, which seem to have been 
overlooked by Przibram in his work(7). 
Bateson(9) described a specimen of Asellus aquaticus which had 
the left antennula supplanted by a mandible. 
Shelford (10) found a cockroach (probably allied to Panesthia sinuata 
Saus), which by dissection proved to have the right maxilla sup- 
planted by a hard chitinized structure which superficially looked like 
a mandible. The left maxilla and both mandibles were normal. 
By closer examination it was found that the abnormal right ‘‘max- 
ila’? was made up of four immovable joints. Shelford, without 
drawing any definite conclusions about the nature of the abnor- 
mality, mentions that another species of Panesthia has been found 
tO possess segmented mandibles in the embryonic stage. 
Osburn(11) describes a male Syrphus arcuatus Fallén (later identi- 
fied as L. perplecus Osburn), in which the large compound eye was 
absent on the left side; a third antenna was found on this side of 
the head behind the normal antenna and entirely separated from this, 
inserted in a separate fossa. The extra antenna was nearly normal 
but was somewhat undersized and lacked the dorsal seta, the arista. 
Osburn mentions the experiments of Herbst with the Crustacea and 
supposes that the eye of the Syrphus had been injured during the 
metamorphosis and had been supplanted by the antenna. 
Przibram (Experimental-Zoologie, 2. Regeneration) later mentions 
the following case, observed by Tornier, as a probable case of homee- 
osis; Tornier(12) cut off the right antenna on a number of larve of 
Tenebrio molitor, which seemed nearly ready for pupation; five of 
these larvee pupated seven days after the amputation and the pupe 
showed a beginning regeneration of the antenne. Four of these 
pup developed into imagoes with normal, regenerated antenne, 
but the fifth imago showed the following peculiar regeneration: 
on the tip of the remaining basal part of the antenna, which showed 
the wound of the amputation on its fourth joint, developed a claw- 
jike formation, which was immovably fixed on the antenna without 
any joint. 
KYrizenecky has in a short paper(13) criticized one of the cases of 
transpositional homeeosis recorded by Przibram, but this criticism 
has no bearing on the present paper. 
Before I give my own observations I wish to bring together from 
Przibram’s tabulation(7) such records of homeosis as are of special 
interest in connection with the present paper, namely, those in 
which tarsuslike formations have been found on the antenne. 
