1897.) Zoology. 235 
frontal enlargements in a large percentage of the skulls of both Mephitis 
and Spilogale from all localities. Merriam (Revision of the Genus 
Spilogale, N. A. Fauna, No. 4, p. 3, 1890) speaks of “ large asymmetri- 
cal postorbital swellings resulting from the presence, in the frontal 
sinuses, of a worm-like endoparasitic arachnid of the genus Penta- 
stoma,” and on p. 4 of the same work, refers to “the large swellings 
produced by the worm-like parasite (Pentastoma or Linguatula) which 
infests the frontal sinuses of more than half the skulls examined.” 
Bangs, in a Review of the Weasels of Eastern North America (Proce. 
Biol. Soc. Washington, Vol. X, p. 1, 1896) speaks of“ the parasite that 
attacks the frontal sinuses of these animals as well as those of their 
relatives the skunks, mink, and otter.” Putorius noveboracensis he 
says “suffers so much that it is hard to get perfect skulls.” See also 
the figures of skulls in Merriam’s Synopsis of the Weasels of North 
America (N. A. Fauna, No. 11, 1896). 
The swellings in the frontal hones of the specimen of Mephitis sub- 
mitted to me are caused by a nematode worm which in every particu- 
lar agrees with Filaroides mustelarum van Beneden (Mém. s. 1. Vers 
Intestinaux, p. 267, 1861), and I have no hesitancy in ascribing it to 
that species. Each of the swellings contained a nest of at least fifteen 
to twenty of the worms. The parasite is common in Europe, occurring 
in the air-passages of several species of Martins and Weasels. It has 
been described and figured in the frontal sinuses of Mustela by Weijen- 
bergh (Arch. Néerlandaises, Tom. III, p. 428, 1868), and von Linstow 
(Arch. Naturg, Jahrg. 39, Bd. I, p. 300, 1873) has described it from 
the ethmoid and frontal bones of Mustela and Putorius. The parasite 
is always, directly or indirectly, connected with the respiratory system. 
The object of this note is to call attention of the occurrence of Fila- 
roides mustelarum in America, and to show that, without doubt, the 
swellings so common in the skulls of American skunks are caused by 
the presence of this nematode in the frontal sinuses ; and that the pre- 
valent frontal enlargements of other American Mustelide are probably 
due to the same parasite—W. McM. Woopworts. 
Museum of Comparative Zéology, 
Cambridge, Mass., Jan. 21, 1897. 
A Peculiar Appendage on the Thelycum of Penzus.'— 
A short preliminary note by Dr. Kishinouye undertakes to show that 
the leaf-like structure first described by Spence Bate in the Challenger 
report on the Macrura as an appendage of the secondary sexual organ 
| The Zoological Magazine, Tokio, VIII, 59. 
