An electron microscope study has been made of octopus and amphibian photoreceptors, after fixing with KMnO(4) and embedding in araldite. What has previously been seen as a single dense stratum bounding the tubular compartments (octopus) or the double membrane discs (rods and cones), now shows a double structure. We interpret this as showing that these tubules and discs have similar bounding sur...

During the present study, we aimed at providing a first look at the elemental composition of the early stages of cephalopods as an approach to their elemental requirements in culture. Essential and non-essential elemental profiles of the European cuttlefish Sepia officinalis, the European squid Loligo vulgaris and the common octopus Octopus vulgaris laboratory hatchlings and wild juveniles were...

Untrained Octopus vulgaris (observers) were allowed to watch conditioned Octopus(demonstrators) perform the task of selecting one of two objects that were presented simultaneously and differed only in color. After being placed in isolation, the observers, in a similar test, consistently selected the same object as did the demonstrators. This learning by observation occurred irrespective of the ...

Surgical treatment for diffusely diseased coronary arteries has been considered to be a relative contraindication for off pump coronary artery bypass (OPCAB) grafting. We report a case of off pump long-onlay-bypass grafting using the left internal mammary artery. To our knowledge, the long-onlay-patch grafting with OPCAB technique has not been previously described. Two sets of Octopus-3 tissue ...

This work reports a genetic data of Octopus vulgaris, marine species of high commercial value, from nineteen localities of Atlantic, Mediterranean and the Adriatic regions. We used mitochondrial DNA cytochrome c oxidase subunit I (COI) gene to investigate the genetic structure of common octopus. Our results indicated a significant genetic structuring in the study area (Phi = 0.136, P <0.001) an...

The common octopus is the most demanded cephalopod species for human consumption. Despite important advances realized recently, main bottleneck commercial production of octopus, Octopus vulgaris , mass mortality paralarvae in first 15–20 days post-hatching (dph), with responsible factors still unknown. Thus, identification limiting culture is, therefore, crucial their aquaculture. This study in...

Since Hunter's (1912) original experiment with rats, it has been shown that many animals can learn to choose correctly between identical shapes even though the signal indicating the correct choice is removed before the animal is allowed to make the choice. The period during which an animal can be kept waiting after the signal has been removed and still make the correct choice varies from specie...