Since the work of DODT1), the photosensitivity of pineal organ of fish has been detected electrophysiologically in some fishes2-5). Furthermore, some structural evidences for the photosensory function are presented by the electron microscopic studies on piscine pineal organs.6-10) However, only a few species of fishes were used in these studies.On the other hand, some observations had been made on the pineal window of deep sea fishes and migratory ones such as tunas and scombrids, taking phototaxis and color change of fish into account11-14). But no detailed histological informations are available on the pineal organ in various species of fishes.The present report deals with histological investigations on the pineal organ of 15 species of teleosts, as the first step in the studies on the pineal organ of fishes. Materials and MethodsThe species used in the present examination are shown in Table 1. Using living fishes, firstly macroscopic observations were made on the pineal window which is found in the dorsal head skin between the larteral eyes. Then fishes were decapitated and entire heads were fixed in 10% neutral formalin, ZENKER-formol, BoulN's or ELFTMAN'S fluids for histological investigation. After fixing for 24-48 hours, the specimens were decal cified by means of electric decalcification, dehydrated in alcohol, and embedded in paraffin.

No abstract

The rectal glands of elasmobranchs perform the function of salt-excreting organs. These glands are smaller and show regressive changes in specimens of the bull shark, Carcharhinus leucas found in fresh-water environment, compared with specimens of this and other species from a marine habitat.

No abstract

Plasma obtained from patients with MCNS in active stage suppressed the ³H-TdR incorporation of autologous or homologous lymphocytes stimulated with PHA-P and E rosette formation, while plasma from patients in remission did not. The depressed mitogenic response of lymphocytes from patients in the active stage significantly improved when the patient’s plasma was substituted for the plasma from inactive MCNS or healthy persons and fetal calf serum. In the preliminary experiment, it was seen that the inhibitory factors were heat stable at 56°C, unadsorbable to charcoal powder and retained in both the permeable and impermeable fractions of collodion bag.