Palæozoic and other Echinoids 1
نویسندگان
چکیده
منابع مشابه
The electrical activity of the radial nerve in Diadema antillarum Philippi and certain other echinoids.
Electrophysiological studies in echinoderms are rare. In echinoids investigations have been made by Takahashi and Sandeman. The former used Diadema setosum, the latter Strongylocentrotus, Tripneustes and Toxopneustes. Takahashi gives a brief account of the electrical concomitant of the photic responses already described in detail by Millott and co-workers. Behavioural studies showed that the ra...
متن کاملA diverse assemblage of Permian echinoids (Echinodermata, Echinoidea) and implications for character evolution in early crown group echinoids
—The Permian is regarded as one of the most crucial intervals during echinoid evolution because crown group echinoids are first widely known from the Permian. New faunas provide important information regarding the diversity of echinoids during this significant interval as well as the morphological characterization of the earliest crown group and latest stem group echinoids. A new fauna from the...
متن کاملComparative Aspects of Superficial Conduction Systems in Echinoids and Asteroids.
SYNOPSIS. The spine-convergence response of sea urchins and the papula (deimal branchia) retraction response of starfish persist after removal of the central nervous system, but are blocked by scratching through the skin. They are mediated therefore by diffuse superficial conduction systems capable of limited spread—to a few centimeters. The spine response does not bend around the ends of a cut...
متن کاملIslam and other Religions
Any student of comparative religion will notice - and seek to identify as well - the points of similarity and difference between various religions. One might even claim that the discipline of “influence studies” has its roots in these discussions of comparison and contrast. However, these discussions persistently fail to address the nuances of particular faiths. Here, I intend to shed some ligh...
متن کاملEast Weddell Sea echinoids from the JR275 expedition
Information regarding the echinoids in this dataset is based on the Agassiz Trawl (AGT) and epibenthic sledge (EBS) samples collected during the British Antarctic Survey cruise JR275 on the RRS James Clark Ross in the austral summer 2012. A total of 56 (1 at the South Orkneys and 55 in the Eastern Weddell Sea) Agassiz Trawl and 18 (2 at the South Orkneys and 16 in the Eastern Weddell Sea) epibe...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Nature
سال: 1913
ISSN: 0028-0836,1476-4687
DOI: 10.1038/091147a0