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the mouth. They are ring-like in figure, with an enclosed disk, and with 

 tegumentary folds at their outlets. The glands and apertures increase in 

 number with age, and the ducts tend to become chitinous. Glands varying 

 somewhat in structure, but evidently similar in kind, exist in species of 

 Linyphiidae, Theridiidae, and Epeiridae. — Mr. Stuart O. Ridley made a 

 communication »On two cases of incorporation by Sponges of spicules foreign 

 to them.« In a species of the genus Ciocalypta, Busk, the dermis contained 

 spicules which belonged to a species of Esperia, and which latter sponge had 

 been obtained in the same haul of the dredge. — In another example of 

 Alehion, spicules also derived from Esperia, were likewise obtained. Thus, 

 the author points out, an element of error might arise from one sponge con- 

 taining skeletal structures accidentally derived from a neighbouring sponge of 

 a different genus and habit. — Prof. Allman called attention to a remark- 

 able Medusa first observed by Mr. W. Sowerby in the fresh-water tank con- 

 taining the Victoria regia at the Botanic Gardens, Regent's Park. He de- 

 scribed the specialities of this small but elegant organism, whose congeners 

 are altogether marine in habit. How the swarms could have come into or 

 been developed in the tank, for the present remains doubtful, for no fresh 

 water had been put into the tank for some years, nor has any sea-water been 

 added, or other material likely to have contained ova been introduced. The 

 name Limnocodium Victoria has been given by Prof. Allman to this hereto- 

 fore unknown form. — A short note from Prof. Lankester concerning 

 this same Medusa was also read, and living specimens were exhibited by 

 Mr. F. Crisp. — Mr. F. M. Campbell communicated a second paper »On 

 the stridulating organs of Steatoda guttata and Linyphia terebricola.« A stri- 

 dulating organ has already been described by Prof. Westering and Mason 

 Wood in certain other spiders ; the present observations demonstrate its exi- 

 stence in both sexes, and the essentials of the structure are now given in 

 detail. — Dr. J. E. Dobson, in »Notes on Aplysia dactylomela«, a spe- 

 cimen obtained at Bermuda, but not distinguishable from the species in- 

 habiting the Cape Verde Islands, showed that there is inequality of size of the 

 right and left moiety in the dental rows of the lingual ribbon, and he de- 

 scribed other structures appertaining to the mandibular plates. — Mr. G. 

 Busk communicated some researches on the Polyzoa collected in the late 

 North Polar Expedition. Several interesting and new forms are given, while 

 the author expressed himself as difi'ering in his determination in certain cases 

 from that arrived at by Prof. Smitt of Stockholm. — A paper »On the Natural 

 Classification of the Gasteropoda« (Part I), by Dr. J. D. Macdonald, was read. 

 He refers to a paper of his published by the Society twenty years ago, wherein 

 sexual characters, lingual dentition and auditory concretion formed the basis 

 of classification. With modifications this is elaborated, and in certain groups 

 additional value is accorded to the lingual and labial dentition. — The sixth 

 contribution to the »Mollusca of the , Challenger' Expedition«, by the Rev. 

 R. Boog Watson, wherein the author treats of the Turretellidae, and de- 

 scribes nine new species, was taken as read. — A paper by Sir John Lub- 

 bock, Bart., M. P., was read, namely, »Observations on Ants, Bees, and 

 Wasps, with a description of a new species of Honey Ant«. In this, his 

 seventh contribution on this subject, Sir John related his fresh experiments 

 on their powers of communication. — J. Murie. 



Druck von Breitkopf und Härtel in Leipzig. 



