ZOOLOGY. 607 



meiits free, without wings and halteres, with pleural processes upon the 

 last two segmeuts." 



(3) Bynchota. — "Insect usually- with imperfect metamorphosis. Head 

 free or broadly united to the thorax, with or without fticetted eyes. 

 Buccal organs usually suctorial. Sucking-tube (in the higher groups) 

 composed of two lateral half-channels (the mandibles), only in the 

 anterior portion inclosed by the labium and its apical multiarticulate 

 palpi, which are united nearly to the apex; at the base by the labrum. 

 Maxillae styliform, without palpi, applied laterally to the mandibles in 

 the channel of the labium or the labrum. Salivary efl'erent duct un- 

 paired, formed by two half-channels of the mandibles closing together 

 from the sides. No 'sucking-stomach.' Thoracic segments free or 

 amalgamated. Four, two, or no wings ; no halteres." 



Relations of the Emhioid Insects. — In a contribution to our knowledge 

 of the Emhiidce, a family of Orthopterous insects, Mr. J. Wood-Mason 

 has added to our knowledge by. describing the various phases of devel- 

 opment of some Embiidce, and expresses his opinion as to the relations 

 of those curious insects. The Emhiidce, bethinks, "undoubtedly belong 

 to the true Orthoplera," but thej" are " in some respects the lowest 

 term, and in others the lowest term but one, of a series represented by 

 the families Acridioidea, Locustidw, Gryllidce, and Phasmatidce;^^ their 

 "resemblances to the much lov,'eY Ptrlidcc, which may well be direct de- 

 scendants of a form closely related to Campodea, are due to their low 

 position in the division of Orthopterous insects to which they belong, 

 and do not imply any such close genetic relationship to them as has been 

 suggested." {Proo. Zool. Soc. London, 1883, pp. 628-634, pi. 56.) 



MOLLUSCOIDS. 



Polyzoans. 



Morphology of Flustra. — The investigation of the marine Bryozoans 

 has been undertaken by W. J. Vigelius, who proposes to publish a 

 monograph on the subject. A treatise on the morphology of Flustra 

 memhranacco-truncata is a precursor of and an introduction to the 

 work. The Flmtrce corroborate the dictum that the mode of growth 

 of the Bryozoan stock is of no value as a means of distinguishing 

 families, for which it has often been used. The nutrient animal and 

 the avicularium are alone distinctly differentiated individuals, for the 

 brood-capsules are simply organs. The nutrient animals may be (1) 

 budding, found on the marginal zone of the colony ; (2) perfect or re- 

 productive forms; (3) resting; and (4) decaying. The last two are only 

 found near the proximal part of the stock, and are much rarer than the 

 others. " The cystid and polypid make up the complete nutrient animal, 

 and in the normal condition consist of integument, nutrient apparatus, 

 and parenchymatous tissue." No nervous system has been distinctly 



