Dicranura vinula, and other Notes. 123 
thoracic segment an “eversible soft tubercle covered 
with short hairs.” That of Nola strigula has glandular 
sternal apertures in the 2nd and 3rd thoracic segmeuts, 
and carries “tubiform appendages near the thoracic 
feet,’ Packard (10). 
Schiiffer (19) describes the sternal prothoracic gland of 
Hyponomeuta evonymella as being divisible into anterior 
and posterior portions, provided with two retractor 
muscles, and furnished with a spiny internal lining. 
The dorsal abdominal glands of Porthesia similis are 
stated by Klemensiewicz (8) to secrete a clear, odourless 
fluid, and the interior of each cell to form a separate 
projection into the lumen of the gland. 
Professor Poulton has told me in conversation, and given 
me permission to mention the fact that the secretion of 
the sternal prothoracic gland of Stawropus fag is acid. 
A large number of other larvee and imagines have been 
described by various authors, particularly Schiffer (18), 
Haase (6), Packard (10, 11), as possessing similar 
glandular structures, but the details of their descriptions 
are not sufficient for purposes of comparison. The above 
statements, however, make it clear that there exists a 
fairly complete series which commences with projecting 
setiparous warts or tubercles surrounding a glandular 
opening, and leads up to invaginated spiny (setiparous) 
tubes placed laterally to the opening of the median gland. 
This evidence appears to me sufficient to justify the sup- 
position that these lateral structures are directly derived 
from setiparous projections of a Cheetopod ancestor, and I 
would maintain that the spines now present in the lateral 
tubes of D. vinula and other species are the actual repre- 
sentatives of original setz. Bernard (1) suggests that 
the ventral parapodium is represented by the tracheate 
leg, that the acicular gland sac of the dorsal parapodium 
gave rise to the trachea itself of the Hexapod, that the 
scattered trachez of Peripatus are derived from ordinary 
setiparous glands, and that the stink-glands of Julus found 
origin in the glands of parapodial setze, the coxal glands, 
perhaps, in acicular gland sacs. The relations which I 
have described above, especially when taken in connection 
with the results of other observers lead me to the con- 
clusion that the glands under discussion are the homo- 
logues of the coxal glands and of the acicular gland sacs 
of Cheetopods, while the lateral appendages (spiny pro- 
