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may be found in a recent number of Botanisches Centralblatt, Bd. 65, No. 4, 1896. It is entitled, Der Reis-Brand und der Setaria-Brand, die Entwicklungsgleider neuer Mutterkornpilze.—Erwin F. SMITH.
Respiration of Trilobites. Dr. C. E. Beecher comments as follows on the probable method of respiration of the trilobite genus, Triarthrus. “No traces of any special organs for this purpose have been found in this genus, and their former existence is very doubtful, especially in view of the perfection of details preserved in various parts of the animal. The delicacy of the appendages and ventral membrane of trilobites and their rarity of preservation are sufficient demonstration that these portions of the outer integument were of extreme thinness, and therefore perfectly capable of performing the function of respiration. Similar conditions occur in most of the Ostracoda and Copepoda, and also in many of the Cladocera and Cirripedia."
“The fringes on the exopodites in Triarthrus and Trinucleus are made up of narrow, oblique, lamellar elements becoming filiform at the ends. Thus they presented a large surface to the external medium, and partook of the nature of gills.” (American Journal Science, April, 1896.)
A Criticism of Mr. Cook's Note on the Sclerites of Spirobolus.--I have read with some interest Mr. Cook's description' of certain lines found upon the rings of a specimen of Spirobolus marginatus, but I am unable to agree with him in the conclusions drawn from them, nor with his remarks relative to the diplopod segment in general. It seems somewhat surprising that Mr. Cook made no examination of the musculature, either of the specimen described or of any other, to determine whether the lines discovered coincided in any way with lines of muscular attachment, an examination that is necessary to give his conclusions more than a very superficial footing. Had he made the examination, it is extremely doubtful whether he would have found this necessary data, since in more or less closely related forms no lines of attachment corresponding to his lines are to be found.
This journal, p. 333.
Indeed there are many facts that he either ignores or of which he is unaware that are far from lending support to his interpretation of the lines. Some of these I have pointed out elsewhere? when considering the subject of the diplopod segmentation. Mr. Cook seems unfortunate in thinking of the greatly overgrown dorsal plate in the diplopod ring as the segment or somite, and in drawing his con parison from the geophilids. Had he examined the conditions occuring in the pauropods and those in Lithobius, Scutigera and scolopendrids, and taken into account some of the ontogenetic facts known regarding diplopods, he doubtless would have plainly seen indications of alternate plates (not segments) having disappeared and of the remaining plates over-growing the segments bebind them, so as to give rise to the anomalous double segments. There would then have been no reason for bringing forward the most decidedly unprogressive supposition, namely, that the double or apparently double condition of the diplopod segment is a condition sui generis unexplainable upon general morphological principles.
With reference to his supposition that alternate leg pairs have disappeared even in the geophilids, the case that he has in mind in mentioning the Chilopoda, I must say there is no evidence whatever. To adduce the geophilid condition as evidence is to adduce the thing to be explained. Therefore, I at least am not able to agree with him in saying that this view is no more fantastic than the old fusion idea of Newport, since the latter has some real ground and many favorable appearances in its support, even though it be incorrect.
-F. C. KENYON. The Sight of Insects.-M. Felix Plateau has been conducting a series of experiments to settle the question as to whether an insect in flight will go through a net the size of whose meshes would offer no obstruction to the passage of the insect. The question has a bearing upon
the difference of vision of Insects and Vertebrates. Mr. Plateau's recent experiments would seem to confirm the statement made by him in 1889 that the vision of insects is obscure as to form, and is adapted more to the perception of movements.
The data upon which the paper is based were acquired by means of ingeniously contrived nettings of various shapes, with meshes 26 to 27 millimeters and 1 to 2 centimeters in size. These nets were placed over attractive lures, such as flowers that insects frequent and in other cases decaying animal matter. The results of the author's observations are given in the following conclusions :
? The morphology and classification of the Pauropoda, Tufts College Studies No. 4.
“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. 0. P. Jenkins in the Proceeds. Calif. Acad. Sci. Vol. V., 1895.
Two new genera and species of fishes, belonging to the family Percophidæ, 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 anthor 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 Polyxenidze, Stemmatoiulidæ, Spirostreptidæ 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.