The editor does not hold responsibility for opinions expressed by correspondents and does not return or correspond with writers of rejected manuscripts. The first letter discusses the importance of adhering to established conventions in the use of metric units, particularly the prefixes mega- and micro-. The author criticizes the use of "micromicron" instead of "micromillimetre" in a translation, emphasizing that "micromicron" should mean a thousandth part of a micron. The second letter supports Darwin's claim that Dean Herbert believed species were created in a highly plastic condition and evolved through intercrossing and variation. The author shares personal evidence from conifers that support this view. The third letter highlights the importance of recognizing Linnaeus' zoological knowledge and philosophy beyond his "Systema Naturae." It discusses a recently published collection of lectures on the animal kingdom delivered by Linnaeus, which reveals his wide zoological knowledge and the practical interest he infused into his work. The Prolegomena, a key part of the lectures, reflects on the vanity and transience of life, emphasizing the struggle for survival and the ultimate return to nothingness.The editor does not hold responsibility for opinions expressed by correspondents and does not return or correspond with writers of rejected manuscripts. The first letter discusses the importance of adhering to established conventions in the use of metric units, particularly the prefixes mega- and micro-. The author criticizes the use of "micromicron" instead of "micromillimetre" in a translation, emphasizing that "micromicron" should mean a thousandth part of a micron. The second letter supports Darwin's claim that Dean Herbert believed species were created in a highly plastic condition and evolved through intercrossing and variation. The author shares personal evidence from conifers that support this view. The third letter highlights the importance of recognizing Linnaeus' zoological knowledge and philosophy beyond his "Systema Naturae." It discusses a recently published collection of lectures on the animal kingdom delivered by Linnaeus, which reveals his wide zoological knowledge and the practical interest he infused into his work. The Prolegomena, a key part of the lectures, reflects on the vanity and transience of life, emphasizing the struggle for survival and the ultimate return to nothingness.