The detailed anatomy, ultrastructure and histology of the olfactory organ of Micropterus salmoides were investigated by a stereo microscope, a light microscope, and a scanning electron microscope. Its external structure shows a tube-like anterior nostril to stick out and a posterior nostril flat to the skin surface. Meanwhile, its internal structure, the olfactory chamber, contains a fan-shaped rosette structure with 9 to 11 lamellae in adult fish over 35 cm in standard length (SL) and two accessory nasal sacs (ethmoidal and lacrimal sacs) were found. Interestingly, the rosette in young fish under 15 cm in SL was a longitudinal structure in parallel with each of 4–5 lamellae. Histologically, the sensory epithelium (SE) on the olfactory chamber consists of 5 types of cells: olfactory receptor neurons, supporting cells, basal cells, lymphatic cells and mucous cells. In contrast, the non-sensory epithelium (NSE) has stratified epithelial cells, lymphatic cells and mucous cells. The mucous cells of the SE are abundant and distributed densely in one row on the outermost superficial surface, but the one of the NSE are less than the SE. From these results, the olfactory characters of M. salmoides may be related with its ecological habit spending in the middle layer of stagnant water contaminated, more or less.

中文翻译：

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大口黑鲈 Micropterus salmoides、Centrarchidae 嗅觉器官的解剖学、超微结构和组织学

用体视显微镜、光学显微镜和扫描电子显微镜研究了鲑鱼嗅觉器官的详细解剖结构、超微结构和组织学。它的外部结构显示出一个管状前鼻孔伸出，后鼻孔平贴皮肤表面。同时，它的内部结构，嗅觉室，包含一个扇形玫瑰花结结构，在标准长度（SL）超过 35 厘米的成年鱼身上有 9 到 11 个薄片，并发现了两个附属的鼻囊（筛窦和泪囊）。有趣的是，SL 中 15 厘米以下幼鱼的玫瑰花结是一个纵向结构，与 4-5 个薄片中的每一个平行。在组织学上，嗅觉室上的感觉上皮 (SE) 由 5 种细胞组成：嗅觉受体神经元、支持细胞、基底细胞、淋巴细胞和粘液细胞。相比之下，非感觉上皮 (NSE) 具有分层的上皮细胞、淋巴细胞和粘液细胞。SE的粘液细胞丰富，在最外表面呈一排密集分布，但NSE的一个比SE少。从这些结果来看，鲑鱼的嗅觉特性可能与其在被污染的死水中间层的生态习性消耗或多或少有关。