. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. 5mm Figure 1. Clavclina mimala, growing on a glass plate, consists of a thorax and an abdomen enclosed in a transparent tunic, ah: abdomen; at: atrial siphon: br: branchial siphon; bs: branchial sac; en: endostyle; st: stolon; th: thorax; tu: Figure 2. Luminescence of Clavelina miniaia evoked by mechani- cal stimulation. The individual is touched by a fine needle. Note the strong luminescence emitted locally on tunic. tonic solution. Three individuals were examined. Each was immersed in distilled water and records of
. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. 5mm Figure 1. Clavclina mimala, growing on a glass plate, consists of a thorax and an abdomen enclosed in a transparent tunic, ah: abdomen; at: atrial siphon: br: branchial siphon; bs: branchial sac; en: endostyle; st: stolon; th: thorax; tu: Figure 2. Luminescence of Clavelina miniaia evoked by mechani- cal stimulation. The individual is touched by a fine needle. Note the strong luminescence emitted locally on tunic. tonic solution. Three individuals were examined. Each was immersed in distilled water and records of relative intensity of light emission were made at 1-min intervals, until light emission was no longer detectable. The thoracic tunic was chosen for microscopic obser- vations, because of its high transparency. The tunic on a glass slide kept at room temperature begins to glow as the seawater evaporates, thus increasing the osmolarity. To establish the source of light emission, the position of flashes in the tunic was observed through an unillumi- nated microscope with a video camera and photomulti- plier (Hamamatsu Photonics C-1000) and recorded on video film (SONY U-Matic VO-5800 Video Recorder). When light was no longer emitted, the tunic cells were illuminated and videotaped with the same apparatus. Cells in the tunic were examined using a Nikon micro- scope with Nomarski differential interference contrast optics. Photographs were taken using Kodak Tri-X (ASA 400) or Kodak Plus-X (ASA 50) film. Results Stimulation evoking luminescence (a) Mechanical stimulation. Mechanical stimulation with a fine needle could evoke luminescence from any part of the tunic of an intact individual. A strong green luminescence appeared locally at the site of stimulation (Fig. 2). The duration varied from 2 to 5 s. (b) Change of ratio o/'K+ ions and Na~* ions. Relative light intensity of light emission was lowest for a K+/Na+ ratio of , and became higher as the proportion of K+ ions was incre
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Keywords: ., bookauthorlilliefrankrat, booksubjectbiology, booksubjectzoology
