The ultrastructure of the merozoites of eimeria tenellawas observed and discribed . the pellicle consist of two layer membranes , the outer membrane was a continous covering enclosing the whole merozoites , while the inner pellicular complex is interrupted at the anterior and the micropore , and thicken to form the polar ring and micropore . there are 24 microtubules under the pellicle of the merozoite which originated from the polar ring , all of them are connected with the polar ring , and extend alongside the inner pellicular complex to the middle of the merozoite . the head of the merozoite consists of a conoid , an apical vesicule and polar ring . the conoid is a hollow truncated cone . the conoid and spical vesicule can stretch and contract . there are three or more rhoptry and a lot of micronemes . the nucleus has nucleolus . and two layer membranes 利用透射电镜对柔嫩艾美耳球虫裂殖子的超微结构进行了观察描述.柔嫩艾美耳球虫裂殖子的表膜由外膜和内膜复合体两层组成，外膜连续，内膜复合体在头部断开形成极环，在其它部位断开形成微孔；裂殖子的膜下微管24根，起始于极环，向后延伸至细胞核处；裂殖子的头部由顶泡、锥体和极环组成，锥体和顶泡可以伸缩；柔嫩艾美耳球虫裂殖子棒状体3个以上，微线数量很多，二者都由电子致密的结构组成；细胞核位于裂殖子的中后部，外被双层膜，有电子致密的核仁和染色质
