Category: Science - Biology
Trilobites are among the most interesting of invertebrate fossils and have long attracted the attention of amateur collectors and men of science. These "three-lobed minerals" have been mentioned or described in books at least since 1698 and now several thousand species are kno...
It can not be said that the new discoveries of appendagiferous trilobites have added greatly to previous knowledge of the systematic position of the group. Probably none will no...
10. part 1, pls. 4, 5.Jaekel has described a specimen of this species obtained from the Middle Cambrian near Tejrovic, Bohemia, which on development showed beneath the test of the axial lobe, certain...
11. PART II.Granting that the trilobite is a simple, generalized, ancient crustacean, it appears justifiable to attribute to it such internal organs as seem, from a study of comparative ana...
13. PART IV.In order to make easily available the evidence on which the present knowledge of the appendages of Triarthrus and _Cryptolithus_ rests, it has seemed wise to publish brief descr...
9. mm. From the center of the notch in the coxopodite to the outer endis 1.5 mm., which, added to the length of the endopodite, 21 mm., makes a distance of 22.5 mm. from the appendifer to the tip of the dactylopodite, showing that if projected str...
8. PART I.The terminology employed in the succeeding pages is essentially the same as that used by Beecher, with two new terms added. Beecher assigned to the various segments of the limbs...
7. Part IV. Description of the appendages ofThe beginning of the search for the limbs of trilobites was coeval with the beginning of scientific study of the group, knowledge of the appendages being essential to the proper...
2. VOLUME VII DECEMBER, 1920Trilobites are among the most interesting of invertebrate fossils and have long attracted the attention of amateur collectors and men of science. These "three-lobed minerals" ha...
3. Part II is a discussion of the internal anatomy of the trilobite and abrief statement of some of the possible habits and methods of life of these animals. Part III, which begins with a survey of the relationships of the trilobites to other Arthrop...
4. Part I. The appendages of trilobites 20The appendages of _Triarthrus_ (see also Part IV) 39 _Triarthrus becki_ Green 39 Historical 40 Restoration of _Triarthrus_ 42 Relation of cephalic appendages to marking on dorsa...
6. Part III. Relationship of the trilobites to otherCrustacea 106 Branchiopoda 106 _Burgessia bella_ Walcott 108 _Waptia fieldensis_ Walcott 108 _Yohoia tenuis_ Walcott 109 _Opabina regalis_ Walcott 109 Summary 109 Copepoda 110 A...
5. Part II. Structure and habits of trilobites 77Internal organs and muscles 77 Alimentary canal 77 _Ceraurus pleurexanthemus_ 79 _Calymene senaria_ 80 _Cryptolithus goldfussi_ 80 Summary 81 Gastric glands 82 Summary 84 Heart...
1. VOLUME VII DECEMBER, 1920