Ceratopsia increase: history and trends

The taxonomic history of the Ceratopsia began in 1876 with the description of Monoclonius crassus Cope followed in 1889 by Triceratops horridus Marsh. After a peak of discovery and description in the 1910s and 1920s resulting from the Canadian dinosaur rush in the province of Alberta and the Central Asiatic Expeditions to Mongolia of the American Museum of Natural History, the study of ceratopsians declined to a low level until the 1990s, when discoveries in China, Montana, Utah, Alberta, and elsewhere, abetted by increased biostratigraphic and phylogenetic precision, led to an unprecedented resurgence of activity. Even Richard C. Fox, along with colleagues from Peking University, joined in the activity, by naming Psittacosaurus lujiatunensis. To place the activity in historical perspective, half of all known ceratopsians have been described since 2003. Despite important finds of basal ceratopsians in China, Mongolia, and Korea, North America continues to dominate ceratopsian, especially ceratopsid, diversity.

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XV. Letter to M. Lacepede, of Paris, on the Natural History of North America

The Philosophical Magazine ◽

10.1080/14786440508676752 ◽

1805 ◽

Vol 22 (86) ◽

pp. 97-103

Author(s):

Benjamin Smith Barton

Keyword(s):

North America ◽

Natural History ◽

History Of

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XX. Discovery of the metamorphosis in the second type of the cirripedes, viz. the lepades, completing the natural history of these singular animals, and confirming their affinity with the crustacea

Philosophical Transactions of the Royal Society of London ◽

10.1098/rstl.1835.0022 ◽

1835 ◽

Vol 125 ◽

pp. 355-358 ◽

Cited By ~ 7

Keyword(s):

North America ◽

Natural History ◽

Sea Water ◽

The Other ◽

External Appearance ◽

The Real ◽

Real Nature ◽

History Of ◽

The Mediterranean ◽

The Waves

The Fourth Memoir, published in my Zoological Researches and Illustrations, No. III. page 69, &c., having first made known the real nature of the Cirripedes , the key of which remained concealed in their metamorphosis, it might have been expected that some naturalist favourably situated to investigate the oceanic tribe of these animals, would have been the first to make the same discovery in regard to these, and thereby complete their natural history. It was scarcely to be expected that the honour of this discovery also should be reserved for the author, fixed to one spot, where none of them naturally exist, and are but casually thrown upon our shores by the waves of the Atlantic, attached to pieces of wreck, or brought into port fixed to the bottoms of ships returning from distant voyages. Fortunately, however, two ships of this description came into this harbour (Cork), one from the Mediterranean, the other from North America, which, not being sheathed with copper, had their bottoms literally covered with Barnacles of the three genera of Lepas , Cineras , and Otion ; and having persons employed expressly for the purpose, numbers of these were brought alive in sea water, amongst which were many with the ova in various stages of their progress, and some ready to hatch, which they eventually did in prodigious numbers, so as to enable him to add the proof of their being, like the Balani, natatory Crustacea in their first stage , but of a totally different facies and structure; a circumstance which determines the propriety of the separation of the Cirripedes into two tribes, and evinces the sagacity of Mr. MacLeay in being the first to indicate that these two tribes, the Balani and Lepades , were not so closely related as generally supposed. The larvæ of the Balani , described in Memoir IV. under the external appearance of the bivalve Monoculi ( Astracoda ), have a pair of pedunculated eyes, more numerous and more completely developed members, approximating to those of Cyclops , and of the perfect Triton ; while, in the present type, or Lepades , the larva resembles somewhat that of the Cyclops , which Müller, mistaking for a perfect animal, named Amymone , and which can be shown to he common to a great many of the Entomostraca ; or the resemblance is still more striking to that of the Argulus Armiger of Latreille, which, in fact, is but an Amymone furnished with a tricuspidate shield at the back.

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