ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 
191 
Polyclads, a seminal bursa. New forms of accessory female copulatory 
organs are to be seen in the investment of spines which is found in the 
bursa copulatrix of P. challengeri , and the pharynx-like muscular fold 
of Stylochoplana sargassicola. Observations on P. Simrothi show that the 
uteri are thickenings of the epithelium of the bursa copulatrix. 
Some critical observations are made on the nomenclature adopted 
by Lang in describing the parts of the male copulatory apparatus. The 
“antrum masculinum” is called the “penial sheath,” but the latter 
name should be reserved for those circular folds which are secondarily 
formed at the proximal end of the antrum. The name of copulatory 
organ should be reserved for that part of the male apparatus which 
serves to convey the sperm. In the simplest case a pyriform muscular 
bladder with a lumen which gradually widens at its proximal end is, in 
other cases, separable into a spherical seminal vesicle, a ciliated ejacu- 
latory duct, and a chitinous penis, while the epithelium of the two first 
divisions, or of one only, or glands which open into it from the exterior, 
form an accessory granular secretion which is mixed with the sperm. 
In these cases it is not correct to speak of the copulatory organ as a 
whole, or the ductus ejaculatorius, or the seminal vesicle as a granular 
gland, for no special diverticulum has been differentiated. 
Parasitic Distoma have been observed in Planocera pellucida, where 
they were encapsuled in the parenchyma, and P. Simrothi , where they 
were free in the intestine. 
The forms described are Planocera pellucida , an account of which 
was first given by Mertens sixty years ago ; it is a holopelagic 
form which has been found in both the Atlantic and Pacific Oceans ; 
P. Simrothi sp. n. was found between the Island of Ascension and the 
Equator ; P. Grubei sp. n. has been found in the Atlantic and southern 
parts of the Indian Ocean • Stylochoplana sargassicola is the name given 
to the Planaria sargassicola of Mertens; well-preserved examples of 
this species were obtained by the ‘ Hirondelle ’ in the Sargasso Sea ; 
Planctoplana challengeri g. et sp. n. was found off New Guinea by the 
‘Challenger’ in 1875; it has very small tentacles, which indicates that 
it is a Planocerid, although it has distinct signs of affinity with the 
Leptoplanidae. A definite diagnosis is given of the genus. 
Systematic Position and Relationships of Temnocephalese.* — Prof. 
W. A. Haswell, who has been continuing his study of Temnocephala,' f 
comes to the conclusion that the Trematode affinities of Temnocephala 
preponderate over the Turbellarian ; at the same time, it has a number 
of characters which distinguish it very broadly from any individual 
Trematode. And, though the large ventral sucker, the excretory sacs, 
and the nervous system may be set down as decidedly Trematode, and 
not Rhabdocoel in character, the author would find little reason for 
finding fault with any one who regarded Temnocephala as an aberrant 
Rhabdocoel, specially modified in accordance with a peculiar mode of life. 
Helminthological Notes from Hawaii. I — Dr. A. Lutz finds that 
Man, in the Hawaii Islands, may be infested by six parasites, one of 
* Abhandl. Naturf. Gesell. Halle, xvii. (1892) pp. 457-60. 
f See this Journal, 1892, p. 486. 
X Centralbl. f. Bakteriol. u. Parasitenk., xiii. (1893) pp. 126-8. 
