Polypide anatomy of hornerid bryozoans (Stenolaemata: Cyclostomatida)

Bryozoans are small colonial coelomates whose colonies are made of individual modules (zooids). Like most coelomate animals, bryozoans have a characteristic body wall composition, including epidermis, extracellular matrix (ECM) and coelothelium, all pressed together. The order Cyclostomatida, however, presents the most striking deviation, in which the ECM and the corresponding coelothelium underlying major parts of the skeletal wall epidermis are “;peeled off” to form an independent membranous sac. The polypide anatomy and ultrastructure of this group is best known from one family, the Crisiidae (Articulata). Here we examined four species from the phylogenetically and ecologically contrasting family Horneridae (Cancellata) from New Zealand. Here we provide the first detailed ultrastructural examination of the hornerid polypide, including tentacles, mouth region, digestive system and the funiculus. We were able to trace continuity and transitions of cell and ECM layers throughout the whole polypide. In addition we identified that the funiculus is a lumen-free ECM cord with two associated muscles, disconnected from interzooidal pores. While agreeing with the general cyclostomate body plan, hornerids have some unique traits that make them worthy of additional study.HighlightsHornerids share a general cyclostomate body plan. The frontal tentacle ECM transitions into oral sphincter ECM, the abfrontal lophophore ECM becomes a septum between coelomic compartments, and the funuculus is a solid ECM cord supplied with muscles.

Some formulas of L. Carlitz on Hermite polynomials

We have used the idea of ‘quasi inner product’ introduced by L. R. Bragg in 1986 to consider generating series∑n=0∞Hn2(x)Hn2(y)tn22n(n!)2studied by L. Carlitz in 1963. The pecularity of the series is that there is(n!)2in the denominator, which has a striking deviation from the usuaI generating series containingn!in the denominator. Our generating function for the said generating series is quite different from that of Carlitz, but somewhat analogous to generating integrals derived by G. N. Watson (Higher Transcendental function Vol.III, P 271-272 for the case of Legendre, Gegenbauer and Jacobi polynomials.

Sequence comparison of glyceraldehyde-3-phosphate dehydrogenases from the three urkingdoms: evolutionary implication

The primary structure of the glyceraldehyde-3-phosphate dehydrogenase from the archaebacteria shows striking deviation from the known sequences of eubacterial and eukaryotic sequences, despite unequivocal homologies in functionally important regions. Thus, the structural similarity between the eubacterial and eukaryotic enzymes is significantly higher than that between the archaebacterial enzymes and the eubacterial and eukarytic enzymes. This preferred similarity of eubacterial and eukaryotic glyceraldehyde-3-phosphate dehydrogenase structures does not correspond to the phylogenetic distances among the three urkingdoms as deduced from comparisons of ribosomal ribonucleic acid sequences. Indications will be presented that the closer relationship of the eubacterial and eukaryotic glyceraldehyde-3-phosphate dehydrogenase resulted from a gene transfer from eubacteria to eukaryotes after the segregation of the three urkingdoms.Key words: glyceraldehyde-3-phosphate dehydrogenase, archaebacteria, protein evolution.