462 ' FR. G. AEATHCOTE. 
Literature. 
But little work has been done on the early development of 
Chilognatha. According to Newport, De Geer was the first to 
watch the development of Julide (6). He observed that 
Julus and Polyxenus were hatched with three pairs of limbs 
and a fewer number of body segments than is possessed by the 
adult animal. 
Savi was the next observer. In 1817, in a paper quoted by 
Newport (11) and which I have not been able to obtain, he 
said that Julus was hatched without limbs. The next observer 
was’ Waga. In 1840, he, in a paper quoted by Newport (11), 
states that the young Julidz are completely apodal at the time 
of hatching. Gervais (8), the next observer, in 1844, gives a 
great deal of fresh information about the later development of 
Chilognatha, but has little to say with regard to the earlier 
stages before hatching. He tells us, however, that Glomeris 
marginata has three pairs of limbs before hatching; that 
Polydesmus complanatus has also three pairs when 
hatched. 
Fabre (7) in 1855, investigated the development of Poly- 
desmus, and describes it as having three pairs of limbs and 
eight body segments, including the head segment, at the time 
of hatching. He also investigated Julus aterrimus, and 
describes it as hatching on the fifteenth day, being then 
apodous and without any organ or appendage, and the shape of 
the body being reniform ; five days afterwards, he tells us, that 
he observed the first traces of body segmentation, and that 
seven days after hatching the animal consisted of eight body 
segments and possessed three pairs of limbs. 
Metschnikoff found that the young of Julus Morreletti 
were hatched with three pairs of limbs (9), while Newport found 
that in Julus terrestris the just hatched young only pos- 
sessed the rudiments of three pairs of limbs, and faint traces 
of the antenna. My own investigations, which were carried 
