The red pigment in the eyes of the squid, blue crab, and horseshoe crab becomes photosensitive when treated with formalin, and bleaches in the light. The resulting change in density is approximately symmetrical around a maximum at 480 mmicro in the blue green. This difference absorption spectrum is in rough agreement with the spectral sensitivity of the cephalopod eye and differs only slightly ...

Animal colour signals used in intraspecies communications can generally be attributed to a composite effect of structural and pigmentary colours. Notably, the functional role of iridescent coloration that is 'purely' structural (i.e., absence of pigments) is poorly understood. Recent studies reveal that iridescent colorations can reliably indicate individual quality, but evidence of iridescence...

Continuous irradiation of Mougeotia with linearly polarized green light (550 nanometers, 0.2 watt per square meter) induces a change in the orientation of its chloroplast from profile to face position, if the electrical vector of the green light is vibrating normal to the cell axis. This change is complete within 25 minutes of the onset of irradiation. In contrast, if the electrical vector of t...

OBJECTIVE To describe the vascular nature and clinical features of idiopathic polypoidal choroidal vasculopathy in Japanese patients. METHODS Patients thought to have idiopathic polypoidal choroidal vasculopathy were examined with binocular ophthalmoscopy, slitlamp biomicroscopy with a contact lens, fluorescein angiography, and indocyanine green angiography. RESULTS From January 1993 to Dec...

The compound eye of the butterfly Papilio xuthus consists of three different types of ommatidia, each containing nine photoreceptor cells (R1-R9). We have found previously that the R5-R8 photoreceptors of type II ommatidia coexpress two different mRNAs, encoding opsins of green- and orange-red-absorbing visual pigments (Kitamoto et al., 1998). Do these cells contain two functionally distinct vi...

An agar medium containing 10% defatted milk has been tested as a diagnostic medium for Pseudomonas aeruginosa and, in particular, for differentiating between P. aeruginosa and P. fluorescens. Only P. aeruginosa colonies gave clear zones due to hydrolysis of casein together with diffused green pigment. Results on milk agar correlated well with the pattern of results from a variety of conventiona...

The wings of four papilionid butterfly species of the nireus group, Papilio bromius, P. epiphorbas, P. nireus and P. oribazus, are marked by blue-green coloured bands surrounded by black margins. The cover scales in the coloured bands contain a violet-absorbing, blue-fluorescing pigment. The fluorescence and absorbance spectra of the nireus group wings are very similar to those of the wings of ...