ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 
473 
half of the body, the shortness of the “ connecting canal ” between the 
intestine and the oviduct, the presence of a pair of glands at the 
entrance to the mouth, and the absence of lateral brandies from the 
posterior part of the intestine. The author gives a detailed account of 
the anatomy of his new species. 
He confirms the view of Zeller that the union of the two individuals 
is a permanent copulation, but corrects him as to the mode, for ho 
states that the vas deferens of one individual opens into the yolk-duct 
of the other, and not into Laurer’s canal. It appears probable that in 
Microcotyle the spermatozoa are passed into a dorsal vagina which leads 
into a canal opening into the yolk-duct. If in Microcotyle there is also 
cross-copulation then the only extraordinary point about Diplozoon is 
that the mode of copulation regular in allied forms is there made 
permanent. 
Structure of Phagocata gracilis.* — Mr. W. M. Woodworth devotes 
the first of his contributions to the morphology of the Turbellaria to the 
study of the remarkable Triclad, for which Dr. Leidy proposed the 
generic name. This worm differs from all known Triclads in possess- 
ing not only the ordinary pharynx, but many additional pharynges 
which are joined to the two lateral trunks of the intestine. Histologi- 
cally they resemble the median pharynx, and differ from it only in 
size. 
The rhabdites are developed in cells which lie in the subhypodermal 
mesenchyma, and these are connected with the hypodermis by fine 
tubular prolongations ; they are ultimately discharged, and new rods are 
constantly being developed in new parent cells ; these last are uni- 
cellular glands, and the rods are their condensed secretions. 
The structureless basement membrane is a product of the hypo- 
dermis ; the pigment is intercellular and occurs in the form of scattered 
granules. The pseudocoelar spaces of the mesenchyma are intercellular 
in origin, and sagittal muscles are directly continuous with processes of 
the mesenchyme cells. The superficial and deeper portions of the 
nervous system are indirectly connected by a marginal nerve, and the 
condition in Phagocata may be intermediate between that of Gunda 
and Rhynchodesmus ; the brain has an anterior and a posterior com- 
missure ; the so-called “ Substanzinseln ” are regarded as intrusive 
connective tissue. 
The vasa deferentia have terminal enlargements and function as 
vesiculse seminales ; the yolk-glands arise by cell proliferation from 
two cell-masses, the parovaria, which are in immediate contact with the 
ovaries. The intimate connection of the parovaria and ovaries indicates 
that the ovary and vitellarium w r ere differentiated from a common 
gland. The so-called uterus is not merely a gland, but a place in which 
the sexual elements are brought together, and fertilization effected. 
Rhynchodesmus terrestris.f — Mr. S. F. Harmer has been able to 
show that this Land Planarian is by no means uncommon in Cambridge. 
It is probable that this animal is much commoner than is usually 
* Bull. Mus. Comp. Zool., xxi. (1891) pp. 1-42 (4 pis.), 
f Proc. Camb. Philos. Soc., vii., pt. ii., 1 p. [separate copy]. 
2 L 
1891. 
