20 DR. BAIRD ON TWO NEW CESTOID WORMS. [Jan. 28, 
14, Caica HaMATOTIS.—Pionus hematotis, Sclat. et Salv.P.Z.S. 
1860, p. 300; Ibis, 1860, p. 401, pl. 13. 
Playa Vicente. These are the only examples of this Parrot I 
have seen, except those obtained by Mr. Salvin, who discovered the 
species in Vera Paz in 1860. 
15, SparuLa cLypPeata (Linn.). 
Cosamaloapam. Noticed by Mr. Salvin as far south as Duemas. 
(See ‘ Ibis,’ 1859, p. 231.) 
16. FuLiGuLA RUFITORQUES, Bp. 
Examples in undress plumage, from Oaxaca. I believe that the 
birds in Senor R. Montes de Oca’s collection, which I referred 
(P. Z. 8S. 1859, p. 369) to F. affinis, were really of this same species. 
3. Description oF Two New Species or Crstoip Worms, 
BELONGING TO THE GENUS Tanta. By W. Barrp, M.D., 
F.L.S. 
(Plate II.) 
1. Tania AMMONITIFoRMIS. (PI. II. figs. 1-7.) 
Head small, somewhat quadrangular ; mouth circular, armed with 
a single circlet of recurved hooklets ; neck nearly of the same size as 
the head. Body increasing gradually in size as it descends from the 
neck, with numerous indistinctly formed segments, and remaining of 
nearly uniform size till it reaches the lower extremity, where it again 
contracts in dimensions, the segments then becoming regularly tzenii- 
form and flat. 
At first sight this entozoon presents a singular and anomalous ap- 
pearance. When first taken it was found rolled up in the form of a 
double helix, with a peculiar hollow in the middle (fig. 1).. Each 
of these helicoid portions, when examined by a low power, presented 
the appearance of an ammonite (fig. 3). When partially unrolled, 
it assumed the form of the shell of a species of Stliquarza (fig. 2). 
The whole body of the animal is hard and rigid, and partially in- 
curved at the edges, giving the under surface a hollow appearance. 
The divisions or rings seen on the body are not distinctly formed 
segments till near the lower extremity, when three or four regular 
teeniiform segments show themselves, as in other species of the genus 
Tenia. The structure of the centre portion of the body is exhibited 
at fig. 4, but the segmented lower extremity has not been repre- 
sented. No trace of genital organs was observed. The head (figs. 5 
and 6) is somewhat tetragonal in shape, and beset on its edges with 
sparsely scattered and small protuberances. The bothria or suck- 
ers are of moderate size, and the mouth is terminal, and surrounded 
with a single crown of amber-coloured recurved hooklets, presenting 
the appearance of siliceous spicula (fig. 7). 
At first sight it is difficult to imagine this anomalous-looking 
entozoon to be a Tenia; but the four bothria or suckers, and the 
