“RAYMOND: NOTES ON THE ONTOGENY OF PARADOXIDES. 235 
in the youngest stages known, becomes proportionately shorter during 
some of the early nepionic stages (pusillus stages), and becomes longer 
again in the neanic and early ephebic stages. The palpebral lobes are 
in general very much longer in young stages than in later ones, but 
many species are primitive in this regard, and retain the long eyes at 
maturity (P. rugulosus group). Most of the adult characteristics are 
assumed at an early age, so that specimens 6-10 mm. long are often 
almost identical in form with the adult; but certain minor features 
such as the lateral extention of the second thoracic segment, persist 
well on into the ephebic stages. 
Application to P: harlani. It will now be seen why the form of the 
brim of this species is so important. The wide brim is a feature 
which, in this genus, is decidedly larval in character, and in such forms 
as are known to have had it, it is lost at an early age, when the cepha- 
lon was 6-10 mm. long. Its retention in large adults like P. harlana 
is most unusual. Another result arrived at above is applicable to 
P. harlani. It was found that the glabellar furrows were not lost by 
the adult, but that, on the contrary, the adult had more furrows than 
the young. None of the very young of P. harlani are known, but the 
smallest glabellas now before us (11 mm. long) show two pairs of 
furrows which cross the glabella and another pair, (No. 2), which are 
faintly indicated at the sides. The small cranidium figured (Plate, 
fig. 3) which is 19 mm. long, shows a similar condition, but the No. 2 
furrows are much more distinct. In some of the largest specimens 
(glabella 100 mm. long) furrows 1 and 2 are both distinct, and most 
specimens with cranidia more than 40 mm. long show all four pairs of 
furrows. In these two features, then, the wide brim and the slow ac- 
quisition of glabellar furrows this species is very primitive. 
The palpebral lobes in the smallest specimen mentioned above 
reach from the glabella back to the occipital furrow, and their chord 
is 6 mm. in length. In specimen No. 22 they meet the glabella, but 
terminate | mm. in front of the occipital furrow, and the chord of the 
lobe is 7mm. In the adult this eye is proportionately much smaller, 
for, on a cranidium 79 mm. long the posterior end of the lobe is 9 mm. 
from the occipital furrow and 8 mm. from the glabella, the chord of 
the lobe being 21 mm. Thus the proportion of the length of the chord 
of the palpebral lobe to the length of the cranidium in the smallest 
specimen is .50, in the second, .32, and in the adult, .26, or a reduction 
of about one half. In common with most other species of Paradoxides, 
P. harlani shows a great lateral extension of the fixed cheeks during 
the process of growth. 
