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"1. A net extended does not arrest the flight of insects in every case."
"2. During flight the insects act as if they did not see the meshes of the net."
"3. A direct passage by flying is always rare. In the great majority of cases the insect hurls itself upon the net where it rests on one of the threads, and then passes through as any other animal would go through an opening which it discovers."
"4. The only explanation possible for these facts rests on the defective vision due to the compound eyes of Insects. The threads of the net produce in the insect an illusion of a continous surface, just as the cross-hatchings of an engraving do for a human eye. The Arthropod believes itself to be confronted by an obstacle, more or less translucent, in which it can perceive no openings." (Bull. Acad. Roy. Sciences Bruxelles, Nos. 9-10. 1895.)
Dr. Baur on my Drawings of the Skull of Conolophus subcristatus Gray.-In the No. of the Naturalist for April (last p. 238), Dr. Baur criticises Steindachner's drawings of the skull of the above species and my copies of them published in the Naturalist for February, p. 149. He says of the former: "These drawings have not been made to show the detailed relations of the different elements of the skull. Especially the regions copied by Cope are drawn quite insufficiently. The sutures between the different elements can not be made out." To this I have to remark that the sutures between the quadrate and adjacent bones are distinctly drawn, and can be made out perfectly well by any one familiar with the subject, but some of the others are less distinct. Dr. Baur then goes on to say that "Prof. Cope's drawing are not exact tracings from Steindachner for he has drawn sutures which do not exist at all in Steindachner's figure. There is no such suture between the postorbital. Pob, and his supertemporal, St., in the actual specimen, nor in Steindachner's drawing.
In Prof. Cope's figure the outer and upper portion of the distal end of the paroccipital process separates the parietal process from the prosquamosal (supratemporal Cope.) This is not the case; the parietal process is always united with the prosquamosal. * The prosquamosal (supratemporal Cope) is also drawn quite incorrect; besides, its true relations cannot be made out at all from Steindachner's figures **"
It will be noticed that in the above criticism nothing is said about the articulation of the quadrate with the exoccipital, which is the
question at issue between us; I alleging that the articulation exists, and Dr. Baur denying it. Dr. Steindacher's figures show conclusively that the articulation exists, as it does in nearly all other Lacertilia, and Dr. Baur has not alleged that this plate is wrong in this particular, or that my tracing of it is not an exact copy. On comparing my tracing with the original again, I find that it is an exact copy, and that if any errors exist they are altogether irrelevant to the question at issue. The separation of the parietal process from the superatemporal is shown in Steindachner's plate, but it may be erroneously, as Baur alleges. The suture separating the postorbital from the supratemporal in my drawing may also be an error, but it represents a feature of Steindachner's drawing, which he did not perhaps intend for a suture, although it looks like it. These two points are obscure to the eye without close examination, and it is probable that Baur is right as to their condition in nature. They however do not discredit the accuracy of the conspicous features of the articulations of the elements with the quadrate, which I find to agree with other Iguanidæ.
Dr. Baur's assumption as to what I" really believe," is not quite correct, as can be easily seen by reading my previous articles. What I have endeavored to show is that until the character of the paroccipital (squamosal Baur) of the Pythonomorpha is explained, I hold that the determination of that element as squamosal as is made by Baur, is premature. I am agnostic, and am open to conviction, but Dr. Baur has not yet convinced me.-E. D. COPE.
Zoological News. The Tokio Zoological Magazine, for 1895, Vol. VII contains an account by R. Mitsukuri of a Japanese species of Hariotta, for which he proposes the name H. pacifica. The type species of this remarkable chimaeroid genus is now in the U. S. Natl. Mus. It was found in deep water off the coast of Virginia and described by Goode and Bean under the name H. raleighana. See Naturalist 1895 p. 375 Plate XIX. The Pacific form agrees with the Atlantic one in general appearance, especially in the elongate muzzle and feeble claspers, but differs in five essential points which are enumerated by the author. The occurrence of this interesting genus in both the Atlantic and Pacific Oceans is an interesting fact.
Recent explorations in the Gulf of California along the coast of Sinaloa have resulted in a collection of fishes, which while yielding 232 species, by no means exhausts the richness of that locality. The collection was sent to Prof. Jordan for identification. Thirty new species were found among the specimens, all of which are described
and figured in the proceedings of the Calif. Acad. Sci. Vol. V. 1895. Among the new fishes described during the past year is Razania makua from the Hawaiian Islands. The species is very rare, only two specimens being known. It is a deep-sea fish by habit, and is especially remarkable for its rapidity in swimming. A colored plate accompanies the description given by Mr. O. P. Jenkins in the Proceeds. Calif. Acad. Sci. Vol. V., 1895.
Two new genera and species of fishes, belonging to the family Percophidae, are reported from Australia, by J. D. Ogilby. They are described by him under the names Centropercis nudivittis and Tropidostethus rothophilus. The latter are surf-fishes, never descending to the bottom, but swimming a few inches beneath the surface of the water. (Proceeds. Linn. Soc. N. S. W. (2) Vol. X. Pt. 2, 1895.)
In an examination of 52 specimens of Vipera berus from Denmark, Mr. Boulenger finds a wide range of individual variation. The differences observed are in the shape of the snout, the scaling of the head, body and tail, size and coloration. The observations as to color confirm those previously made by Geithe in Germany. (Zoologist, 1895.) The same author in a recent classification of the American Box Tortoises in the British Museum, adopts Baur's definitions of species and distinguishes six of which he gives a synopsis. He holds to the generic name of Cistudo although it has been shown that Terrapene has priority. Ann. Mag. Nat. Hist. 1895.)
A New Diplopod Fauna in Liberia. From the west coast of Africa large numbers of Diplopoda are already known, and yet very little of the vast extent of territory has been thoroughly searched for members of this group. In connection with an attempted exploration of Liberia under the auspicies of the New York State Colonization Society, there has been an opportunity for careful collecting in the western part of that country, some of the results of which are here offered. The majority of Liberian Diplopoda belong to the suborder Polydesmoidea. The only other families represented are the Polyxenidæ, Stemmatoiulidæ, Spirostreptide and Spirobolidæ, and these offer no very remarkable novelty in structure or form. This is in strong contrast to the great number and variety of Polydesmoidea; indeed it
1 Edited by Clarence M. Weed, New Hampshire College, Durham, N. H.
has proved necessary to establish genera and families in attempting to properly recognize their structural novelty and diversity. Some of these new groups have already received names, but their characters have been only formally indicated.
Two minute Glomeroid genera were discovered, one of which, Ammodesmus, is the smallest member of the suberder, if not of the entire class. The only species, Ammodesmus granum, is less than two millimetres long, and about half a millimetre broad. A single specimen was secured while collecting minute Oniscidæ, but diligent and repeated search failed to find another. It did result, however, in three specimens of a very distinct, though evidently allied, genus which it is proposed to name Cenchrodesmus. Both genera have the habit of coiling into a sphere. The second segment is enormously enlarged so as to completely conceal the head and first segment when viewed from the side, as well as to cover the space left between the decurved carina of the other segments when the creatures are coiled. Ammodesmus has the dorsum roughened by a transverse row of large papilliform tubercles rising from the posterior part of each segment, while Cenchrodesmus volutus has the segments nearly smooth. The surface of Ammodesmus is rough and dusted with earth. When disturbed it coils up and lies motionless, and is then perfectly concealed, having exactly the appearance of a grain of sand. My specimen would certainly not have been seen had it not been crawling. Cenchrodesmus is pinkish in life Both genera live on the
and mottled with pale horn-color in alcohol. ground under decaying wood or leaves.
This also contains two genera similar in size and general shape, yet evidently distinct, in that Campodesmus has the segments ornamented with two conspicuous clusters of coarse tubercles, while Tropidesmus jugosus has two transverse rows of short longitudinal carinæ, a form of sculpture previously quite unknown in Polydesmoidea. The caring are depressed in both genera, and the dorsal surface is very rough with fine granules and tubercles. Pores are visible on the fifth and seventh segments, but I have been unable to find them on the others. Both forms are denizens of the deepest forests, where the light is so deficient that they are sure to be overlooked unless specially sought for. They are very sluggish in their movements, and are seldom found crawling. When disturbed they coil up into a spiral, and also assume that posi2 " Proc. U. S. Nat. Museum and Annals N. Y. Acad. Science, 1895.
tion in alcohol. The first segment is not enlarged to conceal the head, nor are the anterior segments larger than the others. The general appearance is strikingly different from that of other Diplopoda, the resemblance being rather to certain lepidopterous larvæ.
Familly COMODESMIDÆ, new.
The type of this family is a small, reddish-brown, subcylindrical form, very rare, and also inhabiting the denser parts of the forest. The pore-formula is unique: 5, 7, 9, 12, 15, 17, 18. The pores are located in the front part of the posterior subsegments. The dorsal surface is beset with conic piliferous granules, giving a wooly appearance. last segment is scarcely produced beyond the anal valves, but is rounded off at apex as in many Iulidæ. The head is not concealed by the first segment, which is narrower than the second and somewhat included between the carina of the latter, much as in Scytonotus granulatus (Say). Two other allied genera, also granular and hairy, are found in similar situations in Liberia, but both have the normal poreformula as in Polydesmus. Thelydesmus is nearly black, larger and much more abundant than Comodesmus. The generic name alludes to the fact that the females are in a large preponderance. Although about a hundred females were taken, careful and extended collecting resulted in only four males. The remaining genus is minute and very rare, cylindrical, and without carinæ. The posterior subsegments are abruptly thicker than the anterior, giving the appearance of a series of of discs laid together, whence the generic name, Discodesmus. In the Berlin Museum is another form evidently allied to Thelydesmus, but with broader carinæ and more resemblance to the Pterodesmidæ, to be noted later on. It was collected in the German Colony of Togo by Dr. K. Büttner, and may be known as Xyodesmus planus.
In addition to the above genera there may be referred to this family Cylindrodesmus Pocock, from Christmas Island. It is even more evidently allied to Comodesmus than the other genera mentioned. There is also in my collection a new generic type from the mountains of Java, not closely related to the other genera, but evidently belonging to the same family group.
Family PREPODESMIDÆ, new.
Under this name it is proposed to arrange West African forms hitherto referred either to Paradesmus or to Oxydesmus, from the latter of which they differ in having the apex of the last segment narrow and bituberculate. The affinities of the group seem to be with the Oxydesmidæ, although no connecting links have yet turned up. In a