. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. NON-LUMINOUS CTENOPHORES 359 shown). Light was not produced by Pleurohrachia col- lected at any of the locations included in this study (Fig. 1). Another member of Pleurobrachiidae, Hormiphora califomensis, which was collected from the Santa Barbara Channel, also consistently failed to produce light. For comparison, other luminescent ctenophores tested at the same time produced luminescence for the duration of the stirring. Even when given only a single brief stimulus, luminous species produced bright flashes (Fig. 2A-C), wi
. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. NON-LUMINOUS CTENOPHORES 359 shown). Light was not produced by Pleurohrachia col- lected at any of the locations included in this study (Fig. 1). Another member of Pleurobrachiidae, Hormiphora califomensis, which was collected from the Santa Barbara Channel, also consistently failed to produce light. For comparison, other luminescent ctenophores tested at the same time produced luminescence for the duration of the stirring. Even when given only a single brief stimulus, luminous species produced bright flashes (Fig. 2A-C), with peak intensities of more than X 107 counts/s ( X 105 counts in 20ms). Chemical extraction Assays of calcium-free extracts of Pleurobrachia bachei from the Santa Barbara Channel (Fig. 3) and P. pileus from the Gulf of Maine (not shown) were indistinguish- able from the background signal. All extracts of P/euro- brachia were inert, while in every case positive control extracts from the ctenophores Haeckelia beehleri. Berne cucumis, I'elamen paralle/um (Fig. 3), Bolinopsis infiin- dihuhtm. Beroe gracilis. Kiyohimea aurita. Bathocyroe fosteri. and Bathyctena c/n/ni. and from the hydrozoans Haliscera conica and Obelia sp. (not shown), produced light both during extraction and upon the addition of CaCl;., at intensities up to X 106 counts/s. Photoprotein regeneration Extracts of Pleurobrachia bachei incubated with lucif- erin were not significantly different from those incubated with methanol only, nor were they different from the neg- ative control treatment, which contained only buffer and luciferin (Fig. 4). Regeneration was noted in the positive controls treatments of Haliscera conica, Haeckelia beeh- leri. and Obelia sp. However one positive control replicate (Beroe ciicnmis) showed no luminescence activity after the regeneration, and in some replications, the luminous species used as positive controls (undescribed Mertensiid. Velamen parallelum) gave inconclusive
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Keywords: ., bookauthorlilliefrankrat, booksubjectbiology, booksubjectzoology
