Collections of some 22,000 female and 6000 male Crangon vulgaris were made throughout the year from the shrimp fisheries of the Severn Estuary and Bristol Channel. All animals were measured.The habits of the species are described; it can withstand a wide range of temperature but, though euryhaline, resembles other Decapoda in the inability to withstand low salinity combined with low temperature.Osmo-regulation is apparently largely inhibited at low temperatures and to a greater extent in the males than the females.Growth rate decreases with increasing age; in the female there is no increase in length when moulting from the ' neuter' to the egg-carrying intermoult. The duration of this intermoult, if spawning is successful, is about double that of the normal intermoult under the same temperature conditions. Growth almost ceases in the winter.Secondary sexual characters are described, especially the differences between the endopodites of the pleopods in the two sexes.Females become mature at a minimum length of 45 mm. in the Channel and seldom less than 50 mm. in the Estuary. The effect of the female sexual cycle on the size of the ovary and the form of the pleopods is described. The process of copulation is described; it can occur in the brackish waters of the estuary. Egg-laying always follows within two days of moulting into the egg-carrying condition but eggs are not retained if copulation has not occurred.The females lie on their sides during the act of spawning and the eggs are firmly attached within thirty minutes to the egg-carrying setae on the basipodites of the first to fourth pair of pleopods, then to those on the endopodite of the first pleopod, finally to those on the coxopodites of the last two pairs of pereiopods.

中文翻译：

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布里斯托尔海峡和塞文河口 Crangon Vulgaris L. 的生物学

全年从塞文河口和布里斯托尔海峡的捕虾业收集了大约 22,000 只雌性和 6000 只雄性 Crangon vulgaris。所有动物都进行了测量。描述了物种的习性；它可以承受很宽的温度范围，但是，虽然广盐，但在无法承受低盐度和低温的情况下，它与其他十足目动物相似。渗透调节在低温下明显受到很大抑制，并且在雄性中比雌性更大。增长率随着年龄的增长而降低；在雌性中，从“中性”到带卵的换羽时长度没有增加。如果产卵成功，这种换羽的持续时间大约是相同温度条件下正常换羽的两倍。冬季几乎停止生长。描述了第二性征，特别是两性腹足动物内足节之间的差异。雌性在最小长度为 45 毫米时成熟。在通道中，很少小于 50 毫米。在河口。描述了女性性周期对卵巢大小和腹足形态的影响。描述了交配过程；它可能发生在河口的咸水中。产卵总是在蜕皮后两天内进入产卵状态，但如果没有发生交配，则不会保留卵子。雌性在产卵过程中侧卧，卵子在三十分钟内牢固地附着在卵子上- 在第一至第四对腹足类的担子上携带刚毛，