1884. ] Zoology. 81 
Lord Walsingham writes us: “Noticing your mention of 
Helia americalis as a myrmicophilous Lepidopteron (Am. NAT., 
Oct., 1883, p. 1070), I would remind you of Myrmicocela ochra- 
ceella Tgstr., which is found also in ants’ nests. It is allied to the 
true Tinez. 
ZOOLOGY. 
OWEN ON THE AsPECTS OF THE BODY IN VERTEBRATES AND 
INVERTEBRATES.1'—The pineal and pituitary bodies, with the in- 
fundibulum, constituting what our author styles the conario- 
hypophysial tract, have been the theme of much discussion 
among naturalists. Some have seen in the pituitary, a glan 
secreting the intraventricular fluids of the brain, while others 
have believed it to be a remnant of an obsolete sense-organ. 
To Professor Owen it is neither of these, but is the residuum of 
the deutostome, or invertebrate mouth, opening on the neural 
aspect of the animal and superseded in the vertebrates by a “ tri- 
tostome” or hemal mouth. In proof of this view he shows that 
in the lower mammals the pineal and pituitary bodies and their 
connections are larger and have a less parenchymatous and more 
tubular structure than in man; that in reptiles the pineal produc- 
tion perforates, as a rule, the parietal bone, but in some cases the 
Suture between parietal and frontal; and that in fishes the relative 
Magnitude and tubular character of this transcerebral tract are 
still more marked. In the skate the extension of the pineal part 
reaches beyond the cartilaginous roof of the brain-case, and in all 
Elasmobranchs it is an elongate tube, dilated at its peripheral 
end and maintaining its communication with the third ventricle, 
from the floor of which the infundibulum extends to join the pitu- 
itary body. In the brain of the Chimera the cerebral masses are 
Separated from the optic lobes by cord-like lamella equal in length 
to the structures they separate. These cord-like lamella seem to 
represent the crura cerebri, and the space between them, which is 
traversed by the pineal body and its connections, is the third ven- 
tricle. This structure seems to indicate that the crura cerebri are 
homologous with the parial cords which girt the gullet and con- ` 
nect the fore brain with the hinder masses in invertebrates. In 
the embryos of all vertebrates the pineal extension seems in quest 
of an open or oral outlet, but is checked by the external skin in 
lower forms, and by the cranial roof of the brain in the higher 
ones, 
_ If it be admitted, with the great authority who, following in the 
line of Geoffrey St. Hilaire, advocates the “ Unity of Organiza- 
tion” of the vertebrate and invertebrate kingdoms, that just as 
the umbilicus is the remnant of the protostome or primordial 
Mouth, so the pineal body and its connections are the remnant in 
* Aspects of the Body in Vertebrates and Invertebrates. By Richard Owen. 
London, 1883. 
VOL, Xvi11.—No. 1, 6 
