IDENTITY OF THE NEMATODE WORM                    349

uteri which run parallel for a certain distance, and then become indistinct in the
ovarian coil situated posteriorly. In a gravid female worm the uteri and the
vagina contain fully developed embryos (Plate XXII, Fig. 1) each enclosed in a
flexible vitelline membrane. The embryonated eggs (Plate XXIII, Figs. 6 (a)
and 6 (b)) measure from 39.6 × 28.8 to 43.2 × 36.0 with the membrane. The
microfilariae as seen outside the membrane in a stained smear measure from
126 to 144 microns.

                                                DISCUSSION

Ihle and Ihle-Landenberg [1933] were the first to describe the filarial worm
recovered from " Cascado " of cattle in the Dutch East Indies, for which they
created a new generic name STEPHANOFILARIA, and named the parasite as STEPHA-
NOFILARIA DEDOESI. Wehr [1935] in his revised classification of the superfamily
FILARIOIDEA has included a new family STEPHANOFILARIIDAE for the reception
of the genus STEPHANOFILARIA, Ihle and Ihle-Landenberg [1933]. Another
species of this genus has been described by Chitwood, [1934] as STEPHANOFILARIA
STILESI. Chitwood distinguishes his species from the original species by the
following two characters :—

      1. The arrangements of the cephalic spines, and
       2. The distance of the vulvar orifice of the female
                  from the mouth opening.

The cephalic spines as observed by Chitwood [ 1934 ] in his species are incom-
plete and asymmetric, whereas in the original species they are apparently complete
and symmetric. The writer while studying his new species has found the cephalic
spines completely encircling the base of the oral elevation in some of the speci-
mens, while in others, although the spines have been found in groups, their sym-
metric arrangement does not appear to be lost. Although Chitwood, for the
description of his species, considers the arrangement of the spines as a distinguish-
ing feature, he attaches no particular importance to it from the taxonomic stand-
point. Certain important factors are likely to be involved in consideration of
these spines as having any taxonomic value. It is to be remembered, however,
that the species of STEPHANOFILARIA have so far been found to be distinctly
pathogenic for the bovine skin where their presence induces a very extensive his-
tological changes. The causation of the lesion by these worms depends to a
certain degree on the irritation caused by the constant movements of these spines
in the tissue of the skin. The arrangement of the spines, therefore, cannot re-
main a constant feature when they, in their chronic attempt at destruction of the
skin tissue, are subjected to a severe strain of tissue reaction. In view of these
observations, however, it is to be presumed that under a pressure of excessive
tissue reaction the cephalic spines may either be pressed to lie in groups, or some
of them may so completely be detached as to give the remaining ones an asymmetric