764 
Journal o f Agricultural Research 
Vol. XXX, No. 8 
Fig. 1 .—Heterakis inflexa (after 
Schneider, 1866) 
The views expressed by Dujardin 
(3) and Schneider (13) as regards the 
specific indentity of Ascaridia inflexa 
and A. perspicillum have been generally 
accepted by helminthologists, includ¬ 
ing Railliet (10), who states that this 
species has 10 pairs of papillae, but 
makes no statement as to their arrange¬ 
ment, excepting that 3 pairs are preanal 
and 7 pairs are postanal. Railliet and 
Henry (11), in their paper on the 
classification of the Heterakidae, list 
A. perspicillum as being possibly 
identical with A. inflexa, a similar 
attitude of uncertainty being expressed 
by Skrjabin (14). 
Recently Ascaridia perspicillum has 
been figured by Bavlis and Daubney 
(1) (fig. 2) and by Smit (15) (fig. 3). 
According to the former, there are 10 
pairs of papillae on the tail of the male, 
the first group consisting of 4 pairs of 
ventral papillae, instead of 3 pairs as 
figured by Schneider, the remaining 
papillae agreeing as to number and 
position with those of Schneider. 
Smit, on the other hand, while agreeing 
with Bavlis and Daubney as to the 
number of papillae, shows a somewhat 
different mode of arrangement, since 
he figures 2 ventral and 3 lateral pairs 
of papillae in the second group, as 
compared with 3 pairs of lateral and 
only 1 pair of ventral as figured by 
Schneider and by Bavlis and Daubney. 
The remaining papillae as figured by 
Smit correspond to those figured by 
Schneider. 
The different conceptions as to the 
number and arrangement of the papil¬ 
lae of Ascaridia perspicillum may be 
summarized as follows: 
Schneider 
Baylis and Daubney 
Smit 
Group 1_ 
Group 2_ 
Group 3.. 
3 pairs of ventral papillae_ 
3 pairs of lateral papillae_ 
1 pair of ventral papillae_ 
2 pairs of lateral papillae_ 
4 pairs of ventral papillae_ 
3 pairs of lateral papillae_ 
1 pair of ventral papillae- 
2 pairs of lateral papillae_ 
3 pairs of ventral papillae. 
3 pairs of lateral papillae. 
2 pairs of ventral papillae. 
2 pairs of lateral papillae. 
Fig. 2 .—Ascaridia perspicillum. (After Baylis and 
Daubney, 1922) 
Assuming that Schneider, Baylis and 
Daubney, and Smit were dealing with 
the same species, it will be seen from 
the comparison of their descriptions of 
the papillae that they all agree as to 
the presence of only two lateral papillae 
in the region of the tip of the tail, the 
number of ventral papillae in the an¬ 
terior two groups showing variations. 
Whether the species in question (As- 
Fig. 3 —Ascaridia perspicillum. (After Smit, 
1922) 
