A similar type of tissue has also been described for some goby (Family Gobiidae) species, which may occur in the gonad proper as a '
mesorchial gland' (Colombo and Burighel, 1974; Colombo et al., 1977) or may be located in accessory structure(s) previously referred to as seminal vesicles (Eggert, 1931; Young and Fox, 1937) or sperm duct glands (Miller, 1984) and more recently as accessory gonadal structures, or AGS (Cole and Robertson, 1988) (see Fishelson, 1991 for summary).