FIELDS, W. G., and K. A. THOMPSON. 1976. Ultrastructure and functional morphology of spermatozoa of Rossia pacifica (Cephalopoda, Decapoda). Can. J. Zool. 54: 908-932. The mature spermatozoan of Rossia pacifica consists of acrosome, nucleus, mitochondrial spur, and tail. Anteriorly, the complex acrosome has a cup-shaped depression containing membrane-bound vacuoles. The acrosome is enclosed by a meshwork of longitudinal and circumferential filaments; its invaginated posterior end surrounds juxtanuclear periacrosomal material. The elongated nucleus, of condensed chromatin filaments, encloses lateroposteriorly the proximal and distal centrioles withina centriolar fossa. Mitochondria lie in a separate, spurlike appendage; proximally its lateral margins are continuous with a collarlike annulus. Nine coarse outer fibres surround the 9 + 2 axoneme. They originate from a centriolar ring and diminish in diameter distally, Staining with periodic acid -Schiff demonstrates some glycogen in the mitochondrial spur near its junction with the nucleus.Structural significance and possible functional roles of the various elements are discussed relevant to fertilization. Although this sperm appears intermediate between the more primitive invertebrate sperm type and highly specialized vertebrate sperm, its morphology seems more related to fertilization biology than to phylogenetic position. The singular separateness of areas of energy production and use in R . pacifica sperm and the lengthy energy-transport path may provide unique opportunities for analysis of metabolic processes common to but indecipherable in other sperm. FIELDS, W. G., et K. A. THOMPSON. 1976. Ultrastructure and functional morphology of spermatozoa of Rossia pacifica (Cephalopoda, Decapoda). Can. J. Zool. 54: 908-932.Le spermatozoIde a maturiti, chez Rossia pacifica, contient I'acrosome, le noyau, l'eperon mitochondrial et la queue. Vers I'avant, I'acrosome complexe porte une depression en forme de coupe ou se trouvent les vacuoles reliees i la membrane. L'acrosome est retenu par un rtseau de filaments longitudinaux et circulaires; son extrtmite posterieure invaginee entoure la substance periacrosomienne juxtanuclCaire. Le noyau allonge, constitue de filaments compacts de chromatine, contient, en position posterieure laterale, les centrioles proximal et distal, ainsi qu'une fosse centriolaire. Les mitochondries occupent un appendice sipare, en forme d'eperon; dans la partie proximale de cet appendice, les bordures laterales sont en continuit6 avec un annulus formant une sorte de col. Neuf grosses fibres externes entourent les 9 + 2 axonkmes.Elles prennent leur origine dans un anneau centriolaire et elles s'amenuisent en direction distale. La coloration au I'acide periodique -Schiff revele la presence de glycogene dans l'eperon des mitonchondries, au voisinage de sa jonction avec le noyau.On discute de l'importance structurale et des r6les fonctionnels possibles de ces divers elements dans la fecondation. Bien que ce spermatozo~de apparaisse comme un intermediaire...

Descriptions are given of two specimens of an unusual type of gonatid squid taken from the North Pacific Ocean. A discussion is made of their relationship to two existing genera, Gonatus and Berryteuthis, of the family Gonatidae, and a note is included on a North Pacific gonatid larva that may be a related earlier stage of these two specimens. Because of their size and condition, neither a new genus nor a new species is declared; however, on the basis of these records, it is suggested that there is a need for a redefinition of the genera of the family Gonatidae.

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