part of part of has part has part located in located in forkhead box protein N1 chordate pharynx hematopoietic system immune system pharyngeal gland hemopoietic organ immune organ hemolymphoid system gland digestive system gland ammocoete thymoid UBERON:0009116 Genes: FOXN1 A thymus-like lympho-epithelial structures, in the tips of the gill filaments and the neighbouring secondary lamellae (both within the gill basket) of lamprey larvae. branchial basket