April 1958 – vol. 51, issue 4–164 The items here are largely unchecked reports, and must not be regarded as authenticated records. They are selected, on the present writer's judgment alone, from sources generally found to be reliable. Observers' names are usually omitted in case a report is subsequently rejected, and none of the items will be mentioned in our annual Index. Readers are asked to submit anything of interest as quickly ... This article is only available to subscribed users.To read more, please log in or purchase a subscription.