Neurohæmal Organs in Crustaceans

Abstract

A NUMBER of structures of nervous origin in the higher Crustacea have recently been described under a variety of names, although they show a unity of structure and possibly of function. We wish to propose, tentatively, a common name to denote organs of this type in crustaceans, in order to avoid a needless multiplicity of names for organs which have many features in common. The organs are: the sinus gland of the eyestalk^1,2; part of the pars distalis of the X-organ of the eyestalk^3,4; the sinus plate or post-commissural organ of the tritocerebral region⁵; the pericardial organs of decapods⁶; the dorsal lamellæ of the pericardium of Squilla and the associated system of dorsal trunks⁷; the transverse bar in the ventral blood sinus of the sixth thoracic segment of Squilla and the associated system of median connectives⁸; the apparatus nervi dorsalis cordis of the crayfish⁹; the neuropiles, or punctate substance, which extend over the ligaments of the heart in Palinurus and Scyllarus¹⁰.