Methyl salicylate offers a very good clearing effect on the yolky leech embryo. However, it is not compatible with many biological stains. It is applicable to the fluorescent dye-labeled specimens (fluorescent antibody or TSA) only. To clear the specimen, pass the specimen through an ethanol series (70%- 80% - 90% - 95% - 100% - 100%) for dehydration. Then, place the specimen in methyl salicylate for a few minutes. The specimen should become nearly transparent. Compared to BBBA, methyl salicylate caused less distortion in cell morphology.