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THE POPULAR SCIENCE MONTHLY.

of New England, indicate the enormous transporting power that was concerned in their removal. Long Island lies between 40° 34' and 40° 10' north latitude, and the 39th parallel is supposed to be nearly the southern limit of the drift; and, as a rule, toward its southern limit the drift is composed of small masses of material, but the dimensions of the Long Island bowlders prove that there may be exceptions to this. The bowlders of the island and of New England appear to be similar in kind, dimensions, and distribution, and are believed by Mr. Lewis to have the same general origin. They also indicate but little diminution of the transporting power which distributed the bowlders of New England, and which so thoroughly modified its surface.

A New Entozoon from the Common Eel.—In the American Naturalist Dr. Samuel Lockwood describes a new parasite which he discovered embedded in the fat, or adipose tissue, on the entrails of the common eel. It has a proboscis which it can protrude from, or entirely retract into, its worm-like body, as into a conical sheath. This proboscis when extended is in the form of a cone, and is surrounded by rings of hooklets. At the extremity or point of this cone-like proboscis is a minute pore, which probably serves the purpose of a mouth. It is this spiny-armed organ which the animal forces by a slow motion into the fat, in and upon which it subsists. When the cone-like proboscis is withdrawn into the body of the animal, the forward end has a truncated appearance, and the entozoon is about one-eighth shorter than when the proboscis is extended. At this time the creature is less than a line in length. Dr. Lockwood has named the object Koleops anguilla. The first word, as denoting the habits of the animal, signifies sheathed-head, and the second, as denoting its habitat, is the technical name for the eel. Aside from the fact that this discovery has a general interest as an item of knowledge respecting the internal parasites of animals, it has a special interest to the helminthologist, as it makes the second genus of an order until now limited to one genus. On this point it is better to give the author's own words. Comparing this species with the Echinorhyncus gigas, long known to the student of the Entozoa, Dr. Lockwood says: "As to their ordinal relations, both are members of Owen's second class of the Entozoa, embracing the Sterelmintha or Solid Worms; and both evidently belong to Duvaine's Type IV., Acanthocephala or Spiny Heads, and to Randolph's Order IV., which bears the same name. Now, in this order there is but one genus, namely, Echinorhyncus, already mentioned; therefore we put in the order a new genus, to which we give the name Koleops, meaning sheathed-head, and species anguilla, because found in the common eel." Besides an extended description, the Naturalist gives good illustrative figures of the subject.

Insects and Flowers.—We are indebted to the report in the World for the synopsis of a paper read by Prof. C. V. Riley at the Dubuque scientific meeting, "On a New Genus in the Lepidopterous Family Tincidæ, with Remarks on the Fructification of Yucca"—one of the lily family.

Prof. Riley said that Dr. Engelmann, of St. Louis, had this year discovered that our yuccas must rely on some artificial agency for fertilization. The flowers are peculiarly constructed, so that it is impossible for the pollen to reach the stigma, it being glutinous and expelled from the anthers before the blossoms open. Prof. Riley, in investigating this subject, discovered that there was a small white moth that did the work, and he demonstrated on the black-board how marvellously the little insect was adapted to the purpose. This little moth, which he calls Pronuba yuccasella (yucca's go-between), was hitherto unknown to entomologists, and forms the type of a new genus. It is very anomalous from the fact that the female only has the basal joint of the maxillary palpus wonderfully modified into a long prehensile spined tentacle. With this tentacle, she collects the pollen and thrusts it into the stigmatic tube, and, after having thus fertilized the flower, she consigns a few eggs to the young fruit, the seeds of which her young larvas feed upon. He stated that the yucca was the only entomophilous plant known which absolutely depended for fertilization on a single species of insect, and that insect so remark-