Cyperus japonicus Mak., which has a widespread distribution in subtropical Asia and extends northwards into Europe, was found to be a C4 species based upon its Kranz leaf anatomy, low CO2 compensation concentration and isotopic composition of leaf carbon. A curious variant of the anatomical arrangement of photosynthetic celis is developed in this wetland species. Connected by veins, two groups of Kranz units, one undemeath the abaxial epidermis and the other in the middle of the blade, form elliptical mesophyll channels. This arrangement of Kranz units has been defined as Kranzkette (literally "the chain of garland"). Like Cyperus longus, another C4 species in the genus, the structure and arrangement of chloroplasts in the bundle sheath celis show it to be a NADP-ME type. Starch grains, however, are formed in both mesophyll and bundle sheath celis. This modified C4 Kranz anatomy with large intercellular air spaces within the chlorenchyma suggests that the arrangement of assimilatory celis may be related to gas transport through the large air-spaces.
In addition to Pisier’s counterexample of a non-accessible maximal Banach ideal, we will give a large class of maximal Banach ideals which are accessible. The first step is implied by the observation that a “good behaviour” of trace duality, which is canonically induced by conjugate operator ideals can be extended to adjoint Banach ideals, if and only if these adjoint ideals satisfy an accessibility condition (theorem 3.1). This observation leads in a natural way to a characterization of accessible injective Banach ideals, where we also recognize the appearance of the ideal of absolutely summing operators (prop. 4.1). By the famous Grothendieck inequality, every operator from $L_1$ to a Hilbert space is absolutely summing, and therefore our search for such ideals will be directed towards Hilbert space factorization—via an operator version of Grothendieck’s inequality (lemma 4.2). As a consequence, we obtain a class of injective ideals, which are “quasi-accessible”, and with the help of tensor stability, we improve the corresponding norm inequalities, to get accessibility (theorem 4.1 and 4.2). In the last chapter of this paper we give applications, which are implied by a non-trivial link of the above mentioned considerations to normed products of operator ideals.