PROBLEM TO BE SOLVED: To provide a superimposing port structure of an intermediate breeding basket preventing shellfish from being caught in a lower part of an opening at a time of shellfish replacement work and shipment and capable of reducing work time.SOLUTION: A lid piece 4 can close a mouth part arranged in a ridge line part 3 of a quadrangular pyramid part 2 so as to be opened, includes a superimposing width gradually reduced from an apex part of the quadrangular pyramid part 2 and ending in an inclined and erected ridge line part 9 of a bottom part 1, forms a closure part 10 by seaming a portion in an appropriate length from the apex part, and includes a release part 11 released without seaming a residual portion. When a basket 5 is inclined while the mouth part arranged in the ridge line part 3 of the quadrangular pyramid part 2 faces downward, the release part 11 of the lid piece 4 opens outward and the mouth part naturally opens. By swinging the basket 5, shellfish is discharged while flowing along the inclined and erected ridge line part 9 of the bottom part 1.SELECTED DRAWING: Figure 2【課題】本発明は、貝の入れ替え作業と出荷時に開口部の下部に貝が挟まることがなく、作業時間短縮ができる中間育成籠の重ね口構造を提供する。【解決手段】蓋片４は、四角錐状部２の稜線部３に設けた口部を解放可能に閉塞し得る重なり片であり、前記四角錐状部２の頂部から重なりの幅を徐々に狭くし底部１の傾斜立上がり稜線部９で終わり、前記頂部から適宜長さ部分を縫合して閉塞部１０を形成し、残り部分は縫合せず解放した解放部１１とする。前記四角錐状部２の稜線部３に設けた口部を下向きにして篭体５を傾けると、前記蓋片４の解放部１１が外向きに開き自然に口部が開き、前記篭体５を振ることで、底部１の傾斜立上がり稜線部９に沿って貝が流れるように放出される。【選択図】図２
